507 results on '"Sea temperature"'
Search Results
2. Population and Transcriptomic Changes of the Tropical Fish Parasite Caligus confusus (Copepoda: Caligidae) with Seasonal Variations in Sea Temperature.
- Author
-
Pimentel-Acosta, Citlalic Altagracia, Caña-Bozada, Víctor Hugo, Osuna-Cabanillas, Juan Manuel, Fajer-Ávila, Emma Josefina, Ovando-Vásquez, Cesaré, and Morales-Serna, Francisco Neptalí
- Subjects
- *
SEASONAL temperature variations , *FISH parasites , *COPEPODA , *WATER temperature , *DEMOGRAPHIC change , *OCEAN temperature - Abstract
Fish–parasite systems could be subject to two scenarios under climate change: (i) increased water temperature might enhance parasite metabolism, allowing the parasite to spread rapidly; (ii) parasitism could decrease if the optimal temperature for growth and transmission is exceeded. Sea lice are parasitic copepods commonly found on marine fish in tropical regions, yet their biology remains poorly investigated. In this study, we analyzed the changes in infection levels and the transcriptomic response of the tropical sea louse Caligus confusus to two seasonal seawater temperatures (30 °C, "warm", and 21 °C, "cold"). The prevalence of C. confusus was significantly higher in the colder water. A de novo transcriptomic analysis of C. confusus, the first for a tropical sea louse, revealed 426 over-expressed and 1402 down-expressed transcripts at the lower temperature. In particular, we observed over-expression of transcripts encoding vitellogenins (vit-1, vit-2, vit-4, and vit-6) and matrix metalloproteinases (mmp-2 and mmp-9), which are involved in reproduction and development. These results suggest that the cold tropical season physiologically favors C. confusus and that low temperature favors embryo development, which might ultimately lead to a higher prevalence. It is possible, therefore, that climate change could reduce some tropical sea lice populations during extreme warming events. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
3. Long‐term variability in spawning stock age structure influences climate–recruitment link for Barents Sea cod.
- Author
-
Ottersen, Geir and Holt, Rebecca E.
- Subjects
- *
FISH populations , *FISHERY management , *ATLANTIC cod - Abstract
Fish populations may spawn a vast number of offspring, while only a small and highly variable fraction of a new cohort survives long enough to enter into the fisheries as recruits. It is intuitive that the size and state of the spawning stock, the adult part of the fish population, is important for recruitment. Additionally, environmental conditions can greatly influence survival through vulnerable early life stages until recruitment. To understand what regulates recruitment, an essential part of fish population dynamics, it is thus necessary to explain the impact of fluctuations in both spawning stock and environment, including interactions. Here, we examine if the connection between the environment and recruitment is affected by the state of the spawning stock, including biomass, mean age and age diversity. Specifically, we re‐evaluate the hypothesis stating that recruitment from a spawning stock dominated by young fish and few age classes is more vulnerable to environmental fluctuations. We expand upon earlier work on the Barents Sea stock of Atlantic cod, now with data series extended in time both backwards and forwards to cover the period 1922–2019. While our findings are correlative and cannot prove a specific cause and effect mechanism, they support earlier work and strengthen the evidence for the hypothesis above. Furthermore, this study supports that advice to fisheries management should include considerations of environmental status. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
4. Investigating the Effects of Super Typhoon HAGIBIS in the Northwest Pacific Ocean Using Multiple Observational Data.
- Author
-
Jeon, Jonghyeok and Tomita, Takashi
- Subjects
- *
TYPHOONS , *RAINFALL , *UNDERWATER exploration , *OCEAN , *ALGAL blooms , *OCEAN dynamics - Abstract
Various multi-source observational platforms have enabled the exploration of ocean dynamics in the Northwest Pacific Ocean (NPO). This study investigated daily oceanic variables in response to the combined effect of the 2019 super typhoon HAGIBIS and the Kuroshio current meander (KCM), which has caused economic, ecological, and climatic changes in the NPO since August 2017. During HAGIBIS, the six-hourly wind speed data estimated a wind stress power ( P w ) which strengthened around the right and left semicircles of the typhoon, and an Ekman pumping velocity (EPV) which intensified at the center of the typhoon track. As a result, firstly, the sea temperature (ST) decreased along a boundary with a high EPV and a strong cyclonic eddy area, and the mixed layer depth (MLD) was shallow. Secondly, a low sea salinity (SS) concentration showed another area where heavy rain fell on the left side of the typhoon track. Phytoplankton bloom (PB) occurred with a large concentration of chlorophyll a (0.641 mg / m 3 ) over a wide extent (56,615 km 2 ; above 0.5 mg / m 3 ) after one day of HAGIBIS. An analysis of a favorable environment of the PB's growth determined the cause of the PB, and a shift of the subsurface chlorophyll maximum layer (SCML; above 0.7 mg / m 3 ) was estimated by comprehensive impact analysis. This study may contribute to understanding different individually-estimated physical and biological mechanisms and predicting the recurrence of ocean anomalies. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
5. Population and Transcriptomic Changes of the Tropical Fish Parasite Caligus confusus (Copepoda: Caligidae) with Seasonal Variations in Sea Temperature
- Author
-
Citlalic Altagracia Pimentel-Acosta, Víctor Hugo Caña-Bozada, Juan Manuel Osuna-Cabanillas, Emma Josefina Fajer-Ávila, Cesaré Ovando-Vásquez, and Francisco Neptalí Morales-Serna
- Subjects
crustaceans ,de novo transcriptomes ,sea lice ,sea temperature ,tropical ecosystems ,Biology (General) ,QH301-705.5 ,Genetics ,QH426-470 - Abstract
Fish–parasite systems could be subject to two scenarios under climate change: (i) increased water temperature might enhance parasite metabolism, allowing the parasite to spread rapidly; (ii) parasitism could decrease if the optimal temperature for growth and transmission is exceeded. Sea lice are parasitic copepods commonly found on marine fish in tropical regions, yet their biology remains poorly investigated. In this study, we analyzed the changes in infection levels and the transcriptomic response of the tropical sea louse Caligus confusus to two seasonal seawater temperatures (30 °C, “warm”, and 21 °C, “cold”). The prevalence of C. confusus was significantly higher in the colder water. A de novo transcriptomic analysis of C. confusus, the first for a tropical sea louse, revealed 426 over-expressed and 1402 down-expressed transcripts at the lower temperature. In particular, we observed over-expression of transcripts encoding vitellogenins (vit-1, vit-2, vit-4, and vit-6) and matrix metalloproteinases (mmp-2 and mmp-9), which are involved in reproduction and development. These results suggest that the cold tropical season physiologically favors C. confusus and that low temperature favors embryo development, which might ultimately lead to a higher prevalence. It is possible, therefore, that climate change could reduce some tropical sea lice populations during extreme warming events.
- Published
- 2023
- Full Text
- View/download PDF
6. Influence of the Atlantic Ocean thermal anomaly on the Longsnout seahorse Hippocampus reidi in a Brazilian estuary.
- Author
-
Freret‐Meurer, Natalie V., Fernández, Tatiane C., and Vaccani, Amanda C.
- Subjects
- *
SEA horses , *HIPPOCAMPUS (Brain) , *OCEAN temperature , *WATER temperature , *OCEAN , *ESTUARIES - Abstract
One of the consequences of climate change is an increase in the temperature of the oceans, which is considered to be one of the greatest impacts on biodiversity. Fish may respond to this impact in several ways, including shifts in their patterns of occurrence. The present study investigated the variation in the structure of a H. reidi population between 2015 and 2017 in the northern Guaíba Island area, highlighting a possible relationship to thermal anomaly associated with the El Niño phenomenon. The seahorse population monitoring was performed monthly, recording sex ratio, abundance, juvenile and adult proportion, depth of occurrence, total length and the holdfast which the seahorse were found attached. The influence of the El Niño event on the study population was evaluated by the correlation of the thermal anomaly data reported for the Tropical South Atlantic Index. Seahorse density on northern Guaíba island was positively and significantly correlated with water temperature, but the sex ratio and number of juveniles were not. The diversity of holdfasts used increased over the study period and was inversely proportional to the thermal anomaly. These results suggest that the thermal anomalies caused by the El Niño in the South Atlantic might trigger migration behaviour in the study species, providing a large aggregation during that period in Guaíba island. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
7. Citizen scientists’ dive computers resolve seasonal and interannual temperature variations in the Red Sea
- Author
-
Celia Marlowe, Kieran Hyder, Martin D. J. Sayer, and Jan Kaiser
- Subjects
citizen science ,dive computer ,sea temperature ,Red Sea ,satellite ,in situ comparison ,Science ,General. Including nature conservation, geographical distribution ,QH1-199.5 - Abstract
Dive computers have the potential to provide depth resolved temperature data that is often lacking especially in close to shore, but spatiotemporal assessment of the robustness of this citizen science approach has not been done. In this study, we provide this assessment for the Red Sea, one of the most dived areas in the world. A comparison was conducted between 17 years of minimum water temperatures collected from SCUBA dive computers in the northern Red Sea (23–30° N, 32–39.4° E), satellite-derived sea surface temperatures from the Operational Sea Surface Temperature and Sea Ice Analysis (OSTIA) optimal interpolation product, and depth-banded monthly mean in-situ temperature from the TEMPERSEA dataset, which incorporates data originating from several in-situ recording platforms (including Argo floats, ships and gliders). We show that dive computer temperature data clearly resolve seasonal patterns, which are in good agreement in both phase and amplitude with OSTIA and TEMPERSEA. On average, dive computer temperatures had an overall negative bias of (–0.5 ± 1.1) °C compared with OSTIA and (–0.2 ± 1.4) °C compared with TEMPERSEA. As may be expected, increased depth-related biases were found to be associated with stratified periods and shallower mixed layer depths, i.e., stronger vertical temperature gradients. A south-north temperature gradient consistent with values reported in the literature was also identifiable. Bias remains consistent even when subsampling just 1% of the total 9310 dive computer datapoints. We conclude that dive computers offer potential as an alternative source of depth-resolved temperatures to complement existing in situ and satellite SST data sources.
- Published
- 2022
- Full Text
- View/download PDF
8. Time series covering up to four decades reveals major changes and drivers of marine growth and proportion of repeat spawners in an Atlantic salmon population.
- Author
-
Harvey, Alison, Skaala, Øystein, Borgstrøm, Reidar, Fjeldheim, Per Tommy, Christine Andersen, Kaja, Rong Utne, Kjell, Askeland Johnsen, Ingrid, Fiske, Peder, Winterthun, Synne, Knutar, Sofie, Sægrov, Harald, Urdal, Kurt, and Alan Glover, Kevin
- Subjects
- *
TIME series analysis , *OCEAN temperature , *ATLANTIC salmon , *LIFE history theory , *SALMON , *LEPEOPHTHEIRUS salmonis , *PEDICULOSIS , *CORAL bleaching - Abstract
Wild Atlantic salmon populations have declined in many regions and are affected by diverse natural and anthropogenic factors. To facilitate management guidelines, precise knowledge of mechanisms driving population changes in demographics and life history traits is needed.Our analyses were conducted on (a) age and growth data from scales of salmon caught by angling in the river Etneelva, Norway, covering smolt year classes from 1980 to 2018, (b) extensive sampling of the whole spawning run in the fish trap from 2013 onwards, and (c) time series of sea surface temperature, zooplankton biomass, and salmon lice infestation intensity.Marine growth during the first year at sea displayed a distinct stepwise decline across the four decades. Simultaneously, the population shifted from predominantly 1SW to 2SW salmon, and the proportion of repeat spawners increased from 3 to 7%. The latter observation is most evident in females and likely due to decreased marine exploitation. Female repeat spawners tended to be less catchable than males by anglers.Depending on the time period analyzed, marine growth rate during the first year at sea was both positively and negatively associated with sea surface temperature. Zooplankton biomass was positively associated with growth, while salmon lice infestation intensity was negatively associated with growth.Collectively, these results are likely to be linked with both changes in oceanic conditions and harvest regimes. Our conflicting results regarding the influence of sea surface temperature on marine growth are likely to be caused by long‐term increases in temperature, which may have triggered (or coincided with) ecosystem shifts creating generally poorer growth conditions over time, but within shorter datasets warmer years gave generally higher growth. We encourage management authorities to expand the use of permanently monitored reference rivers with complete trapping facilities, like the river Etneelva, generating valuable long‐term data for future analyses. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
9. Impacts of River Discharge on the Sea Temperature in Changjiang Estuary and Its Adjacent Sea.
- Author
-
Shen, Hui, Zhu, Ye, He, Zhiguo, Li, Li, and Lou, Yingzhong
- Subjects
ESTUARIES ,HYPOXIA (Water) ,COASTS ,TERRITORIAL waters ,WATER quality ,WATER depth ,REGIONS of freshwater influence - Abstract
Freshwater plume at the Changjiang River (CR) mouth are essential to the coastal water quality and ecosystem because they can cause estuary stratification and hypoxia, potentially deteriorating the water environment. Furthermore, the advection heat transport is modulated by increasing anthropogenic effects. A comprehensive understanding of the influence of river discharge on the three-dimensional sea temperature, fronts and thermal stratification in the CR estuary remains lacking. A well-calibrated numerical model using Regional Ocean Modeling Systems (ROMS) is used to investigate the impacts of CR discharge on the sea temperature in coastal zones. Model results show that the amplitude and spatial distribution of the heating or cooling rate can be influenced by CR freshwater, especially in frontal areas. Specifically, the large runoff flow will reduce the heating or cooling rate in shallow waters (<20 m) near the CR estuary, whereas it has an opposite effect on the Zhoushan islands region (>20 m). Generally, the effect of the freshwater discharge on the upper layer is greater than on the bottom layer, and the runoff has a positive correlation to the intensity of the frontal zones in the CR estuary, though this relationship is weakened in autumn because of the weak intensity of the frontal zone. Note that seawater thermal stratification and its seasonal variation can be regulated by runoff; thermal stratification will be strengthened in abundant runoff conditions and weakened in scarce runoff conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
10. Time series covering up to four decades reveals major changes and drivers of marine growth and proportion of repeat spawners in an Atlantic salmon population
- Author
-
Alison Harvey, Øystein Skaala, Reidar Borgstrøm, Per Tommy Fjeldheim, Kaja Christine Andersen, Kjell Rong Utne, Ingrid Askeland Johnsen, Peder Fiske, Synne Winterthun, Sofie Knutar, Harald Sægrov, Kurt Urdal, and Kevin Alan Glover
- Subjects
Atlantic salmon ,marine growth ,salmon lice ,sea temperature ,veteran spawners ,zooplankton ,Ecology ,QH540-549.5 - Abstract
Abstract Wild Atlantic salmon populations have declined in many regions and are affected by diverse natural and anthropogenic factors. To facilitate management guidelines, precise knowledge of mechanisms driving population changes in demographics and life history traits is needed. Our analyses were conducted on (a) age and growth data from scales of salmon caught by angling in the river Etneelva, Norway, covering smolt year classes from 1980 to 2018, (b) extensive sampling of the whole spawning run in the fish trap from 2013 onwards, and (c) time series of sea surface temperature, zooplankton biomass, and salmon lice infestation intensity. Marine growth during the first year at sea displayed a distinct stepwise decline across the four decades. Simultaneously, the population shifted from predominantly 1SW to 2SW salmon, and the proportion of repeat spawners increased from 3 to 7%. The latter observation is most evident in females and likely due to decreased marine exploitation. Female repeat spawners tended to be less catchable than males by anglers. Depending on the time period analyzed, marine growth rate during the first year at sea was both positively and negatively associated with sea surface temperature. Zooplankton biomass was positively associated with growth, while salmon lice infestation intensity was negatively associated with growth. Collectively, these results are likely to be linked with both changes in oceanic conditions and harvest regimes. Our conflicting results regarding the influence of sea surface temperature on marine growth are likely to be caused by long‐term increases in temperature, which may have triggered (or coincided with) ecosystem shifts creating generally poorer growth conditions over time, but within shorter datasets warmer years gave generally higher growth. We encourage management authorities to expand the use of permanently monitored reference rivers with complete trapping facilities, like the river Etneelva, generating valuable long‐term data for future analyses.
- Published
- 2022
- Full Text
- View/download PDF
11. Varying growth rates of a marine eel, the whitespotted conger (Conger myriaster), are explained by the interaction between seasonal temperature and prey availability.
- Author
-
Mu, Xiuxia, Zhang, Chongliang, Xu, Binduo, Ji, Yupeng, Xue, Ying, and Ren, Yiping
- Subjects
- *
PREY availability , *POPULATION dynamics , *SUSTAINABLE fisheries , *WATER temperature , *SEASONS , *FISHERY management , *OCEAN temperature - Abstract
Whitespotted conger (Conger myriaster) is a commercially important species in East Asia; however, the fisheries stock has drastically declined in recent years. Environmental changes are assumed to have profound impacts on the growth of this species, yet the mechanisms that regulate growth remain poorly understood. Here, we used otolith measurements to establish a 9-year growth chronology for whitespotted conger in the Yellow Sea and evaluated the effects of environmental variables on inter-annual variability in growth. Linear mixed-effects models were used to explain growth variation with abiotic and biotic variables, including seasonal water temperature, prey availability, and population density, and to assess age-dependent responses in growth and the interactions between abiotic and biotic factors. The results indicated that the growth of whitespotted conger was positively correlated with seasonal water temperature (except autumn) and prey abundance per capita, and the contribution of sea water temperature was more important than prey availability to explain growth variation. The model detected significant negative interactions between spring sea temperature and prey availability, indicating a higher degree of temperature-dependent growth when prey availability was low. Our findings imply that the growth of whitespotted conger is less influenced by food availability. This study provided the first evidence for the joint effects of abiotic and biotic factors on the growth variation of whitespotted conger, and the information is key to understanding population dynamics, and will help shape the sustainable management of fisheries. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
12. Co-occurrence of contaminants in marine fish from the North East Atlantic Ocean: Implications for human risk assessment
- Author
-
Quang Tri Ho, Michael S. Bank, Atabak M. Azad, Bente M. Nilsen, Sylvia Frantzen, Stepan Boitsov, Amund Maage, Tanja Kögel, Monica Sanden, Livar Frøyland, Rita Hannisdal, Helge Hove, Anne-Katrine Lundebye, Ole Jakob Nøstbakken, and Lise Madsen
- Subjects
Seafood ,Mercury ,POPs ,Sediment ,Sea temperature ,Human exposure ,Environmental sciences ,GE1-350 - Abstract
Marine fish from the North East Atlantic Ocean (NEAO) are nutrient rich and considered a valuable economic resource. However, marine fish are also a major dietary source of several contaminants, including persistent organic pollutants (POPs) and heavy metals. Using one of the world’s largest seafood datasets (n > 25,000 individuals), comprising 12 commercially important fish species collected during 2006–2019 in the NEAO, we assessed the co-occurrence of elements and POPs, and evaluated potential risks to human consumers. Several positive correlations between concentrations of mercury (Hg), dioxins, polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were observed. Concentrations of Hg, dioxins, PCBs and PBDEs increased from North to South and associations between marine sediment contamination, sea temperature, and fish Hg and POPs concentrations were identified using multi-linear regression (MLR) models. In general, Hg concentrations in fillet and liver of fish were positively associated with increases in both sediment contamination and sea temperature. POPs concentrations in both fillet and liver were positively associated with increases in sediment contamination, and only POPs concentrations in the liver of benthopelagic and demersal species were found to be positively correlated with sea temperature. Using a probabilistic approach to estimate human contaminant exposure from seafood, we showed that intake of pelagic species posed the highest risk of dioxins and dioxin-like PCBs (DL-PCBs) exposure, while intake of benthopelagic and demersal species posed the highest risk of Hg exposure. This study can serve as a model to further understand the distribution, co-occurrence, and trends of contaminants in seafood harvested from the NEAO and their potential risks to human consumers.
- Published
- 2021
- Full Text
- View/download PDF
13. Effect of Sea Temperature on Crude Oil Spill Condition - Simulator Pisces II.
- Author
-
Jarząbek, Dorota and Drwięga, Kinga
- Published
- 2021
- Full Text
- View/download PDF
14. Research on the relationship between seawater temperature changes and the start-up of characteristic towns in coastal cities based on spatial features.
- Author
-
Xi, Jiaying and Bao, Honglin
- Abstract
Climate change is becoming one of the most serious environmental problems in today’s society. It is the East China Sea and the adjacent Northwest Pacific that have a major impact on China’s climate, and they have become a global concern in recent years. The seawater temperature of each sea layer influences each other. The ocean can transfer the heat accumulated through the heat exchange of the ocean air to the atmosphere, and promote the movement of the atmosphere through path changes. Heat affects the circulation of the atmosphere, thereby affecting climate change. The regulation of seawater temperature is an important item in oceanographic research, which can directly reflect global climate change and the distribution of the overall characteristics of the global ocean. In some areas, the level of surface temperature depends on the surface temperature and the geographical distribution of the area. Therefore, accurate measurement of sea surface temperature is very important for ocean temperature research and has a wide range of practical value. Starting from innovative urban tourism resources, we will explore the current status of tourism resource development, such as innovation and entrepreneurship, humanities and history, natural landscapes, and facilities. It is convenient for unique city trips in characteristic towns of coastal cities. In other words, tourism functions and community characteristics are unified, and organic functions and industrial characteristics and functional complexity overlap. Analyze the development of tourism resources in characteristic towns in coastal cities, and put forward specific development suggestions “Innovation and Entrepreneurship + Cultural Tourism” Smart Tourism and the integration of “Industry, Research, Innovation, and Learning”. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
15. When cooling is worse than warming: investigations into the thermal tolerance of an endemic reef fish, Boopsoidea inornata.
- Author
-
Allison, C, Muller, C, Childs, A-R, Froneman, W, Bailey, LA, and Potts, WM
- Subjects
- *
ENDEMIC fishes , *REEF fishes , *THERMAL stresses , *OCEAN temperature , *GLOBAL warming , *FISHERY products - Abstract
Recent investigations suggest that global warming is likely to alter temperature regimes along the southeastern coastline of South Africa through the increased frequency of upwelling events. Identifying thermal thresholds is fundamental in predicting the response of marine ectotherms to rapidly changing ocean temperatures. The aim of this study was to determine the thermal tolerance of the endemic sparid Boopsoidea inornata. To achieve this, 20 wild fish were captured from near Noordhoek in Gqeberha (Port Elizabeth). The fish were exposed to laboratory-simulated upwelling and heat-plume conditions until sublethal endpoints were identified to estimate the critical lower (CTmin) and critical upper (CTmax) thermal limits, respectively. During the simulated cooling or heating events, the opercular beat (OB) rates were recorded, their sublethal endpoints (loss of equilibrium) were identified, and their CTmin and CTmax were estimated. Breakpoint analyses of the OB rates identified the lower and upper thermal stress limits to occur at an average of 9 °C and 25 °C, respectively. The CTmin was estimated to be 7.8 °C and the CTmax 30 °C. When compared with in situ temperatures, these limits suggest that B. inornata is susceptible to small reductions in the minimum temperature. Given that the frequency and magnitude of upwelling events are expected to increase in response to global warming, this may have significant consequences for this and other sympatric, resident species. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
16. Divers as Citizen Scientists: Response Time, Accuracy and Precision of Water Temperature Measurement Using Dive Computers
- Author
-
Celia Marlowe, Kieran Hyder, Martin D. J. Sayer, and Jan Kaiser
- Subjects
citizen science ,dive computer ,sea temperature ,accuracy ,response time ,precision ,Science ,General. Including nature conservation, geographical distribution ,QH1-199.5 - Abstract
There is a lack of depth-resolved temperature data, especially in coastal areas, which are often commonly dived by SCUBA divers. Many case studies have demonstrated that citizen science can provide high quality data, although users require more confidence in the accuracy of these data. This study examined the response time, accuracy and precision of water temperature measurement in 28 dive computers plus three underwater cameras, from 12 models. A total of 239 temperature response times (τ) were collected from 29 devices over 11 chamber dives. Mean τ by device ranged from (17 ± 6) to (341 ± 69) s, with significant between-model differences found for τ across all models. Clear differences were found in τ by pressure sensor location and material, but not by size. Two models had comparable τ to designed-for-purpose aquatic temperature loggers. 337 mean data points were collected from equilibrated temperatures in hyperbaric chamber (n = 185) and sea (n = 152) dives, compared with baseline mean temperature from Castaway CTDs over the same time period. Mean bias, defined as mean device temperature minus baseline temperature, by model ranged from (0.0 ± 0.5) to (−1.4 ± 2.1) °C and by device from (0.0 ± 0.6) to (−3.4 ± 1.0) °C. Nine of the twelve models were found to have “good” accuracy (≤0.5 °C) overall. Irrespective of model, the overall mean bias of (−0.2 ± 1.1) °C is comparable with existing commonly used coastal temperature data sets, and within global ocean observing system accuracy requirements for in situ temperature. Our research shows that the quality of temperature data in dive computers could be improved, but, with collection of appropriate metadata to allow assessment of data quality, some models of dive computers have a role in future oceanographic monitoring.
- Published
- 2021
- Full Text
- View/download PDF
17. Impacts of River Discharge on the Sea Temperature in Changjiang Estuary and Its Adjacent Sea
- Author
-
Hui Shen, Ye Zhu, Zhiguo He, Li Li, and Yingzhong Lou
- Subjects
Changjiang estuary ,Changjiang diluted water ,sea temperature ,numerical model ,Naval architecture. Shipbuilding. Marine engineering ,VM1-989 ,Oceanography ,GC1-1581 - Abstract
Freshwater plume at the Changjiang River (CR) mouth are essential to the coastal water quality and ecosystem because they can cause estuary stratification and hypoxia, potentially deteriorating the water environment. Furthermore, the advection heat transport is modulated by increasing anthropogenic effects. A comprehensive understanding of the influence of river discharge on the three-dimensional sea temperature, fronts and thermal stratification in the CR estuary remains lacking. A well-calibrated numerical model using Regional Ocean Modeling Systems (ROMS) is used to investigate the impacts of CR discharge on the sea temperature in coastal zones. Model results show that the amplitude and spatial distribution of the heating or cooling rate can be influenced by CR freshwater, especially in frontal areas. Specifically, the large runoff flow will reduce the heating or cooling rate in shallow waters (20 m). Generally, the effect of the freshwater discharge on the upper layer is greater than on the bottom layer, and the runoff has a positive correlation to the intensity of the frontal zones in the CR estuary, though this relationship is weakened in autumn because of the weak intensity of the frontal zone. Note that seawater thermal stratification and its seasonal variation can be regulated by runoff; thermal stratification will be strengthened in abundant runoff conditions and weakened in scarce runoff conditions.
- Published
- 2022
- Full Text
- View/download PDF
18. A 7-Year Lag Precipitation Teleconnection in South Australia and Its Possible Mechanism
- Author
-
Lingli Fan, Huade Guan, Wenju Cai, C. P. Rofe, and Jianjun Xu
- Subjects
precipitation prediction ,southern annular mode ,sea temperature ,supergyre ,drought ,Goyder’s line ,Science - Abstract
Precipitation teleconnections with large-scale ocean–atmosphere oscillation systems provide useful information for water management. Here, we present a 7-year lag response in South Australia (SA) precipitation to the Southern Annular Mode (SAM) in a positive Interdecadal Pacific Oscillation (IPO) phase. This teleconnection between a positive SAM phase and increased SA precipitation, and vice versa, statistically consists of three sequential steps: a 27-season lag positive correlation between sea subsurface potential temperature (SSPT) to the south of SA and SAM, a zero-season lag positive correlation between sea surface temperature (SST) and SSPT, and a 2-season positive lag correlation between SA precipitation and sea surface temperature. Physically, this teleconnection seems to be associated with a supergyre circulation of the southern hemisphere oceans, which transfers SAM signal via subsurface potential sea temperature in the central south Pacific to the south of SA in 27 seasons during the positive IPO phase. Practically, this teleconnection provides a 7-year-lead drought precursor for rain-fed agriculture planning in SA. However, the teleconnection disappears in negative IPO phases. The oceanic pathway via the supergyre suggested in this study provides a basis to predict when this 7-year teleconnection may resume in the future based on observation and/or modeling.
- Published
- 2020
- Full Text
- View/download PDF
19. The Effects of Depth-Related Environmental Factors on Traits in Acropora cervicornis Raised in Nurseries
- Author
-
Claudia Patricia Ruiz-Diaz, Carlos Toledo-Hernández, Juan Luis Sánchez-González, and Brenda Betancourt
- Subjects
restauration ,coral farm ,Acropora cervicornis ,sea temperature ,light levels ,Hydraulic engineering ,TC1-978 ,Water supply for domestic and industrial purposes ,TD201-500 - Abstract
Populations of Acropora cervicornis, one of the most important reef-building corals in the Caribbean, have been declining due to human activities and global climate change. This has prompted the development of strategies such as coral farms, aimed at improving the long-term viability of this coral across its geographical range. This study focuses on comprehending how seawater temperature (ST), and light levels (LL) affect the survival and growth of A. cervicornis fragments collected from three reefs in Culebra, Puerto Rico. These individuals were fragmented into three pieces of the similar sizes and placed in farms at 5, 8, and 12 m depth. The fragments, ST and LL were monitored for 11 months. Results show that fragments from shallow farms exhibit significantly higher mortalities when compared to the other two depths. Yet, growth at shallow farms was nearly 24% higher than at the other two depths. Corals grew fastest during winter, when temperature and LL were lowest, regardless of the water depth. Fragment mortality and growth origin were also influenced by reef origin. We conclude that under the current conditions, shallow farms may offer a slight advantage over deep ones provided the higher growth rate at shallow farms and the high fragment survival at all depths.
- Published
- 2022
- Full Text
- View/download PDF
20. Distribución de temperatura y salinidad en campañas oceanográficas recientes en el Pacífico Tropical Oriental de Costa Rica.
- Author
-
Mora-Escalante, Rodney E., Lizano, Omar G., Alfaro, Eric J., and Rodríguez, Alejandro
- Subjects
- *
GENERAL circulation model , *OCEAN dynamics , *COLD (Temperature) , *WATER , *SALINITY - Abstract
Introduction: In Costa Rica, studies done in the Eastern Tropical Pacific or ETP are important because of their interaction/relationship with the Eastern Tropical Pacific Seascape, a known multinational conservation initiative. The present study describes the physical parameters of sea temperature and salinity around Cocos Island and its environment, the ETP, using CTD profiles. Methods: Data were obtained in April 2008, March 2009, April 2010, July 2011 and March 2012 near this island. Latitudinal and longitudinal transects were also done during October 2010 and March 2011 in a broader Costa Rican ETP region. In July 2012, three latitudinal transects were done around Cocos Island. Records were obtained using a CTD, measuring conductivity, temperature and pressure, among other variables. Results: Tropical Surface Water was observed in the upper 50m, showing temperatures above 25°C and salinities below 33psu. Below the surface waters, Subsurface Subtropical Water was detected below a 60m depth, showing temperatures colder than 25°C and salinities around 35psu. The transition between these waters was around 50-60m in depth. Temperature and salinity results were related with the atmosphere conditions observed, in which ETP variability was strongly influenced by the Inter Tropical Convergence Zone migration. Conclusions: This study also showed that reanalysis data from the HYCOM-NCODA general circulation model are comparable and in a good agreement with the CTD profiles. Temperature and salinity HYCOM data also reproduced, in general terms, the main characteristics of CTD data, having some small differences in the deeper levels. This reanalysis data set could also be used to study the tropical ocean dynamics, in wider ETP regions and for different seasons. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
21. Variabilidade da Velocidade do Vento e Influências Oceânicas: Uma Abordagem Para Fins de Geração de Energia Elétrica no Nordeste do Brasil.
- Author
-
Palmeira Cavalcanti, Enilson, Barbosa da Silva, Bernardo, Rodrigues da Silva, Vicente de Paulo, and Chaves Filho, José Batista
- Subjects
OCEAN temperature ,LA Nina ,ELECTRIC power production ,WIND power ,WIND power plants - Abstract
Copyright of Anuario do Instituto de Geociencias is the property of Universidade Federal do Rio de Janeiro, Instituto de Geociencias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2020
- Full Text
- View/download PDF
22. Influence of temperature and salinity on hydrodynamic forces
- Author
-
A. Escobar, V. Negro, J.S. López-Gutiérrez, and M.D. Esteban
- Subjects
Sea temperature ,Salinity ,Hydrodynamic forces ,Wave action ,Offshore wind farms ,Ocean engineering ,TC1501-1800 - Abstract
The purpose of this study is to introduce an innovative approach to offshore engineering so as to take variations in sea temperature and salinity into account in the calculation of hydrodynamic forces. With this in mind, a thorough critical analysis of the influence of sea temperature and salinity on hydrodynamic forces on piles like those used nowadays in offshore wind farms will be carried out. This influence on hydrodynamic forces occurs through a change in water density and viscosity due to temperature and salinity variation. Therefore, the aim here is to observe whether models currently used to estimate wave forces on piles are valid for different ranges of sea temperature and salinity apart from observing the limit when diffraction or nonlinear effects arise combining both effects with the magnitude of the pile diameter. Hence, specific software has been developed to simulate equations in fluid mechanics taking into account nonlinear and diffraction effects. This software enables wave produced forces on a cylinder supported on the sea bed to be calculated. The study includes observations on the calculation model's sensitivity as to a variation in the cylinder's diameter, on the one hand and, on the other, as to temperature and salinity variation. This software will enable an iterative calculation to be made for finding out the shape the pressure wave caused when a wave passes over will have for different pile diameters and water with different temperature and salinity.
- Published
- 2016
- Full Text
- View/download PDF
23. Interannual variability in the ocean and atmosphere in the 1980s and early 1990s
- Author
-
Hassanzadeh, Smaeyl
- Subjects
551.5 ,Atmospheric pressure ,Sea level ,Sea temperature - Published
- 1998
24. Population genetic structure and selective pressure on the mitochondrial ATP6 gene of the Japanese sand lance Ammodytes personatus Girard.
- Author
-
Deng, Zhaochao, Wang, Xiuliang, Xu, Shengyong, Gao, Tianxiang, and Han, Zhiqiang
- Abstract
Thermoregulation has been suggested to influence mitochondrial DNA (mtDNA) evolution. Previous studies revealed that the mitochondrial protein-coding genes of fish living in temperate climates have smaller dN / dS (Non-synonymous substitution rate/Synonymous substitution rate) than tropical species. However, it is unknown whether different geographic populations of one fish species experience stronger selective pressures between cold and warm climates. The biological characteristics of the Japanese sand lance, Ammodytes personatus in the North-western Pacific is well-suited for assessing the performance of mtDNA evolution among separate geographic populations. In this study, we focused on the mitochondrial ATP6 gene of A. personatus using 174 individuals from eight different sea temperature populations. Two distinct haplotype lineages and a significant population structure (P = 0.016) were found in this species. The frequencies of the two lineages varied with the changes of annual sea temperature. The southern lineage (lineage A, dN / dS = 0.0384) showed a larger dN / dS value than the northern lineage (lineage B, dN / dS = 0.0167), suggesting that sea temperature greatly influences the evolution of the two lineages. The result provides robust evidence of local adaptation between populations in A. personatus. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
25. Seasonal and Interannual Variations of Sea Temperature Influenced by Galápagos Islands in Eastern Tropical Pacific Ocean.
- Author
-
Xu, Fanghua, Huang, Xing, Chen, Yue, Huang, Xiaomeng, Lu, Youyu, and Zhao, Peng
- Subjects
OCEAN temperature ,SEASONAL temperature variations ,OCEAN currents ,SIMULATION methods & models - Abstract
The sea surface temperature and surface currents during 1993–2016 based on satellite remote sensing, along with the ocean temperature and currents during 1993–2013 from a data assimilative ocean simulation product, are analyzed to investigate the influence of the Galápagos Islands (GI) in the eastern tropical Pacific on the sea surface temperature. Variations of the cold core west of the GI are quantified by TC − TW, TC − TE, and the cold core area (CCA), where TW, TC, and TE are the sea surface temperature to the west of the cold core, in the cold core, and to the east of the GI, respectively. TC − TE and the CCA show a stronger influence of the GI in boreal fall than in spring, in contrast to TC − TW, which shows a stronger influence in spring than in fall. All three indices show weaker (stronger) GI's influence during El Niño (La Niña) years, but only CCA and TC − TE have significant correlations of −0.66 and 0.61 with the Niño3 index. Variations of TC − TW are related to that of upwelling immediately the west of the GI. Variations of TC − TE and CCA are related to that of the spatial distributions of the upper ocean temperature, the advection of temperature by the horizontal currents, specifically the north branch of the South Equatorial Current, and upwelling in the eastern tropical Pacific. Key Points: Two new indices are defined to quantify the influence of Galápagos Islands on SST in Eastern Tropic PacificNew indices show stronger (weaker) Islands' influence in boreal fall (spring) and during La Niña (El Niño) yearsVariations of the Islands' influence are related to distributions of background temperature, upwelling, and surface currents [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
26. Sea temperature influences accumulation of tetrodotoxin in British bivalve shellfish.
- Author
-
Dhanji-Rapkova, Monika, Teixeira Alves, Mickael, Triñanes, Joaquin A., Martinez-Urtaza, Jaime, Haverson, David, Bradley, Kirsty, Baker-Austin, Craig, Huggett, Jim F., Stewart, Graham, Ritchie, Jennifer M., and Turner, Andrew D.
- Published
- 2023
- Full Text
- View/download PDF
27. The impact of LNG offshore terminal on sea temperature and sea currents in the northern Adriatic Sea
- Author
-
JELIĆ MRČELIĆ, GORANA, JURIĆ, MAJDA, SUPIĆ, NASTJENJKA, and DUTOUR SIKIRIĆ, MaMATHIEU thieu
- Subjects
the Adriatic Sea ,LNG terminal ,Interdisciplinary Natural Sciences ,marine environment ,sea temperature ,sea currents ,ROMS model ,Adriatic Sea ,Traffic and Transport Technology ,Biotechnology - Abstract
The aim of this paper is to simulate the impact of a potential offshore LNG terminal on sea temperature (in autumn and spring/ summer) and sea currents (in autumn/winter) at three different depths (at the sea surface, at 25 m depth and at the seabed) in the northern Adriatic Sea from 14 November 2015 to 06 August 2016 using the Regional Ocean Modelling System (ROMS) model. The location of the potential offshore LNG terminal Istria (in the northern Adriatic Sea) was selected using the visual PROMETHEE method. The potential LNG terminal uses seawater for LNG heating and the seawater cooled to a temperature of 9°C returns to the marine environment. Although the differences in sea temperature with and without the discharge fit within normal temperature ranges, the simulations show that the discharge changed the speed and direction of sea currents at the sea surface not only in the wider northern Adriatic, but in the entire Adriatic. This is probably due to the specific circulation in the Adriatic, where cold water affects the geostrophic balance, an important part of the circulation field that depends on density (a function of salinity and temperature). Atmospheric conditions in the broader vicinity of the LNG terminal would also be affected by redistribution of air-sea fluxes due to changes in surface temperature. Changes in circulation would alter environmental conditions by redistributing nutrients, oxygen, etc. Further multi-year simulations of changes in the circulation system are needed, but other physical parameters (density, salinity, river inflow...) should also be included in the simulations to determine the cumulative impact of a potential LNG terminal on the marine environment.
- Published
- 2023
28. Investigating the Effects of Super Typhoon HAGIBIS in the Northwest Pacific Ocean Using Multiple Observational Data
- Author
-
Jonghyeok Jeon and Takashi Tomita
- Subjects
General Earth and Planetary Sciences ,Northwest Pacific Ocean ,Kuroshio current meander ,mesoscale cyclonic eddy ,typhoon HAGIBIS ,wind stress power ,Ekman pumping velocity ,sea temperature ,sea salinity ,phytoplankton bloom - Abstract
Various multi-source observational platforms have enabled the exploration of ocean dynamics in the Northwest Pacific Ocean (NPO). This study investigated daily oceanic variables in response to the combined effect of the 2019 super typhoon HAGIBIS and the Kuroshio current meander (KCM), which has caused economic, ecological, and climatic changes in the NPO since August 2017. During HAGIBIS, the six-hourly wind speed data estimated a wind stress power (Pw) which strengthened around the right and left semicircles of the typhoon, and an Ekman pumping velocity (EPV) which intensified at the center of the typhoon track. As a result, firstly, the sea temperature (ST) decreased along a boundary with a high EPV and a strong cyclonic eddy area, and the mixed layer depth (MLD) was shallow. Secondly, a low sea salinity (SS) concentration showed another area where heavy rain fell on the left side of the typhoon track. Phytoplankton bloom (PB) occurred with a large concentration of chlorophyll a (0.641 mg/m3) over a wide extent (56,615 km2; above 0.5 mg/m3) after one day of HAGIBIS. An analysis of a favorable environment of the PB’s growth determined the cause of the PB, and a shift of the subsurface chlorophyll maximum layer (SCML; above 0.7 mg/m3) was estimated by comprehensive impact analysis. This study may contribute to understanding different individually-estimated physical and biological mechanisms and predicting the recurrence of ocean anomalies.
- Published
- 2022
- Full Text
- View/download PDF
29. Marked annual coral bleaching resilience of an inshore patch reef in the Florida Keys: A nugget of hope, aberrance, or last man standing?
- Author
-
Gintert, Brooke E., Manzello, Derek P., Enochs, Ian C., Kolodziej, Graham, Carlton, Renée, Gleason, Arthur C. R., and Gracias, Nuno
- Subjects
CORAL bleaching ,PLATFORM reefs ,CORAL mortality ,CORAL communities - Abstract
Annual coral bleaching events, which are predicted to occur as early as the next decade in the Florida Keys, are expected to cause catastrophic coral mortality. Despite this, there is little field data on how Caribbean coral communities respond to annual thermal stress events. At Cheeca Rocks, an inshore patch reef near Islamorada, FL, the condition of 4234 coral colonies was followed over 2 yr of subsequent bleaching in 2014 and 2015, the two hottest summers on record for the Florida Keys. In 2014, this site experienced 7.7 degree heating weeks (DHW) and as a result 38.0% of corals bleached and an additional 36.6% were pale or partially bleached. In situ temperatures in summer of 2015 were even warmer, with the site experiencing 9.5 DHW. Despite the increased thermal stress in 2015, only 12.1% of corals were bleached in 2015, which was 3.1 times less than 2014. Partial mortality dropped from 17.6% of surveyed corals to 4.3% between 2014 and 2015, and total colony mortality declined from 3.4 to 1.9% between years. Total colony mortality was low over both years of coral bleaching with 94.7% of colonies surviving from 2014 to 2016. The reduction in bleaching severity and coral mortality associated with a second stronger thermal anomaly provides evidence that the response of Caribbean coral communities to annual bleaching is not strictly temperature dose dependent and that acclimatization responses may be possible even with short recovery periods. Whether the results from Cheeca Rocks represent an aberration or a true resilience potential is the subject of ongoing research. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
30. Tracking shifts in Atlantic mackerel ( Scomber scombrus) larval habitat suitability on the Northeast U.S. Continental Shelf.
- Author
-
McManus, M. Conor, Hare, Jonathan A., Richardson, David E., and Collie, Jeremy S.
- Subjects
- *
ATLANTIC mackerel , *HABITATS , *MARINE species diversity , *ZOOPLANKTON , *PREDATION - Abstract
Climate change has altered the oceanographic environment and subsequently the habitats of marine species. Fish and invertebrate populations' responses to habitat include movement with latitude and depth to remain within their fundamental niches. The northwest Atlantic mackerel ( Scomber scombrus) population has fluctuated over the last century due in part to changes in the environment. We used species distribution models to understand the influence of the physical (temperature) and biological (zooplankton) environment on mackerel larval abundance, and how such relations have determined larval habitat suitability in the Northeast U.S. Shelf. Atlantic mackerel larval presence and abundance correlated with sea temperature and copepod abundances, suggesting that larval survival may be sensitive to specific temperatures and zooplankton prey. Predicted abundances were spatially interpolated to estimate Atlantic mackerel larval suitable habitat. Metrics for habitat quality indicate that the Mid-Atlantic Bight has become less suitable over time. Since the 1970s, the proportion of Northeast U.S. Shelf suitable habitat located in the Mid-Atlantic Bight has decreased, as southern New England and the western Gulf of Maine regions have become more suitable. Habitat suitability within the Northeast U.S. Shelf has shifted northeast: from the Mid-Atlantic Bight-southern New England border towards the northeast portion of southern New England. While total Northeast U.S. Shelf habitat suitability has decreased since the 1970s, the decline in the time series trend was not statistically significant. Thus, while select ecoregions have decreased in habitat suitability, larval habitat does not appear to be the only contributor to decreases in the U.S. Atlantic mackerel contingent. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
31. Increasing Greenhouse Gas Emissions: Impacts on the Marine Environment
- Author
-
Allsopp, Michelle, editor, Page, Richard, editor, Johnston, Paul, editor, and Santillo, David, editor
- Published
- 2009
- Full Text
- View/download PDF
32. The Initial Errors in the Tropical Indian Ocean that Can Induce a Significant 'Spring Predictability Barrier' for La Niña Events and Their Implication for Targeted Observations
- Author
-
Qian Zhou, Xu Wang, Wansuo Duan, Xiang Li, and Ziqing Zu
- Subjects
Atmospheric Science ,Sea temperature ,geography ,Indian ocean ,Throughflow ,La Niña ,geography.geographical_feature_category ,Downwelling ,Climatology ,Forecast skill ,Environmental science ,Predictability ,Channel (geography) - Abstract
Initial errors in the tropical Indian Ocean (IO-related initial errors) that are most likely to yield the Spring Prediction Barrier (SPB) for La Nina forecasts are explored by using the CESM model. These initial errors can be classified into two types. Type-1 initial error consists of positive sea temperature errors in the western Indian Ocean and negative sea temperature errors in the eastern Indian Ocean, while the spatial structure of Type-2 initial error is nearly opposite. Both kinds of IO-related initial errors induce positive prediction errors of sea temperature in the Pacific Ocean, leading to under-prediction of La Nina events. Type-1 initial error in the tropical Indian Ocean mainly influences the SSTA in the tropical Pacific Ocean via atmospheric bridge, leading to the development of localized sea temperature errors in the eastern Pacific Ocean. However, for Type-2 initial error, its positive sea temperature errors in the eastern Indian Ocean can induce downwelling error and influence La Nina predictions through an oceanic channel called Indonesian Throughflow. Based on the location of largest SPB-related initial errors, the sensitive area in the tropical Indian Ocean for La Nina predictions is identified. Furthermore, sensitivity experiments show that applying targeted observations in this sensitive area is very useful in decreasing prediction errors of La Nina. Therefore, adopting a targeted observation strategy in the tropical Indian Ocean is a promising approach toward increasing ENSO prediction skill.
- Published
- 2021
33. Marine Heat Waves Detection in Climate Warming Seas: Their Evolution in the NW Mediterranean Sea
- Author
-
European Commission, Agencia Estatal de Investigación (España), Martínez, Justino, Ruchon, Loiuse, García-Ladona, Emilio, Ballabrera-Poy, Joaquim, Pisano, Andrea, Leonelli, Francisca Elisa, Kersting, Diego K., European Commission, Agencia Estatal de Investigación (España), Martínez, Justino, Ruchon, Loiuse, García-Ladona, Emilio, Ballabrera-Poy, Joaquim, Pisano, Andrea, Leonelli, Francisca Elisa, and Kersting, Diego K.
- Abstract
[EN] Extreme and prolonged increases in the sea temperature, a marine heatwave (MHW), are detected by comparison with historical values at each location and time of year. Thus, the correct estimation of reference values is key in detecting marine heatwaves. In temporally separated epochs comparison, it is necessary to consider two contributions to the evolution of extreme events: the underlying trend in temperature and its sudden changes. Following the definition of Hobday (2016), we compare the detected MHW in case of correcting or not the climatological trend in the definition of the reference values. We use 38 years of the surface temperature of the Mediterranean Sea provided by the Copernicus service. This work is centered around the Columbretes Islands marine reserve, where there is a coastal sea temperature measurement station integrated into the T-MedNet network. This allows us to have a glimpse of the effect at different depths but with shorter time series. The results show that if the long-term trend is not removed from the reference, then the number of events is underestimated in the first years of the series and overestimated in the last ones regardless of the length of the series. The influence of climate change on the alteration of marine ecosystems caused by the MHWs does not seem to be caused by the increased frequency of MHWs, but rather by the fact that the MHWs take place in an increasingly hot sea, acting on biological systems having greater thermal stress, [ES] El aumento extremo y prolongado de la temperatura del mar, una ola de calor marina (MHW), se detecta por comparación con los valores históricos en cada localización y época del año. Así, el correcto establecimiento de los valores de referencia es una tarea clave en la detección de MHW. Al comparar diferentes épocas es necesario considerar dos contribuciones a la evolución de los episodios extremos: la tendencia subyacente de la temperatura y los cambios súbitos de la misma. Siguiendo la definición de Hobday (2016), comparamos las MHW detectadas en caso de corregir o no la tendencia climatológica en la definición de los valores de referencia. Para ello empleamos 38 años de temperatura superficial del mar Mediterráneo proporcionados por el servicio Copernicus. El trabajo se centra alrededor de la reserva marina de las islas Columbretes, donde existe una estación costera de medición de la temperatura del mar integrada en la red T-MedNet. Esto permite vislumbrar el efecto a diferentes profundidades aunque con series temporales más cortas. El resultado es que no corregir la tendencia al definir la referencia subestima el número de eventos detectados en los primeros años de la serie y los sobreestima en los últimos, independientemente de la longitud de la serie. La influencia del cambio climático en la alteración de los ecosistemas marinos debido a las MHW no parece deberse al incremento en la frecuencia de las mismas, sino a que éstas tienen lugar en un mar cada vez más caliente, actuando sobre sistema biológicos con mayor estrés térmico
- Published
- 2022
34. Propagation of thermohaline anomalies and their predictive potential along the Atlantic water pathway
- Author
-
Barcelona Supercomputing Center, Langehaug, Helene R., Ortega Martín, Nuria, Counillon, François, Matei, Daniela, Maroon, Elizabeth, Barcelona Supercomputing Center, Langehaug, Helene R., Ortega Martín, Nuria, Counillon, François, Matei, Daniela, and Maroon, Elizabeth
- Abstract
We assess to what extent seven state-of-the-art dynamical prediction systems can retrospectively predict winter sea surface temperature (SST) in the subpolar North Atlantic and the Nordic seas in the period 1970–2005. We focus on the region where warm water flows poleward (i.e., the Atlantic water pathway to the Arctic) and on interannual-to-decadal time scales. Observational studies demonstrate predictability several years in advance in this region, but we find that SST skill is low with significant skill only at a lead time of 1–2 years. To better understand why the prediction systems have predictive skill or lack thereof, we assess the skill of the systems to reproduce a spatiotemporal SST pattern based on observations. The physical mechanism underlying this pattern is a propagation of oceanic anomalies from low to high latitudes along the major currents, the North Atlantic Current and the Norwegian Atlantic Current. We find that the prediction systems have difficulties in reproducing this pattern. To identify whether the misrepresentation is due to incorrect model physics, we assess the respective uninitialized historical simulations. These simulations also tend to misrepresent the spatiotemporal SST pattern, indicating that the physical mechanism is not properly simulated. However, the representation of the pattern is slightly degraded in the predictions compared to historical runs, which could be a result of initialization shocks and forecast drift effects. Ways to enhance predictions could include improved initialization and better simulation of poleward circulation of anomalies. This might require model resolutions in which flow over complex bathymetry and the physics of mesoscale ocean eddies and their interactions with the atmosphere are resolved. Significance Statement In this study, we find that dynamical prediction systems and their respective climate models struggle to realistically represent ocean surface temperature variability in the easter, Acknowledgments. The research leading to these results has received funding from the Blue-Action Project (European Union’s Horizon 2020 research and innovation program, Grant 727852), the Trond Mohn Foundation with the project Bjerknes Climate Prediction Unit (BCPU, Grant BFS2018TMT01), the NordForsk under the Nordic Centre of Excellence (ARCPATH, 76654), and from the Bjerknes Centre with the project SKD MEDEVAC. The research leading to these results has also received funding from the German Federal Ministry of Education and Research (BMBF) through the JPI Climate/JPI Oceans NextG-Climate Science-ROADMAP (FKZ: 01LP2002A; DM and Norwegian Grant 316618/JPIC/JPIO-04; HRL and NK and ANR-19-JPOC-003; JM). PO was funded by the Spanish Ministry for the Economy, Industry and Competitiveness through the grant RYC-2017-22772. SY also receives financial support from the Danish National Center for Climate Research (NCKF). The National Center for Atmospheric Research is a major facility sponsored by the U.S. National Science Foundation (NSF) under Cooperative Agreement 1852977. EM is supported by the U.S. NSF Office of Polar Programs Grant 1737377. The prediction simulations using EC-EARTH anomaly initialization system were performed by SMHI on resources provided by the Swedish National Infrastructure for Computing (SNIC)., Peer Reviewed, "Article signat per 16 autors/es: H. R. Langehaug, P. Ortega, F. Counillon, D. Matei, E. Maroon, N. Keenlyside, J. Mignot, Y. Wang, D. Swingedouw, I. Bethke, S. Yang, G. Danabasoglu, A. Bellucci, P. Ruggieri, D. Nicolì, and M. Årthun", Postprint (published version)
- Published
- 2022
35. Optimum Temperatures for Net Primary Productivity of Three Tropical Seagrass Species
- Author
-
Catherine J. Collier, Yan X. Ow, Lucas Langlois, Sven Uthicke, Charlotte L. Johansson, Katherine R. O'Brien, Victoria Hrebien, and Matthew P. Adams
- Subjects
net primary productivity ,thermal stress ,sea temperature ,climate change ,tropical seagrass ,Cymodocea serrulata ,Plant culture ,SB1-1110 - Abstract
Rising sea water temperature will play a significant role in responses of the world's seagrass meadows to climate change. In this study, we investigated seasonal and latitudinal variation (spanning more than 1,500 km) in seagrass productivity, and the optimum temperatures at which maximum photosynthesis and net productivity (for the leaf and the whole plant) occurs, for three seagrass species (Cymodocea serrulata, Halodule uninervis, and Zostera muelleri). To obtain whole plant net production, photosynthesis, and respiration rates of leaves and the root/rhizome complex were measured using oxygen-sensitive optodes in closed incubation chambers at temperatures ranging from 15 to 43°C. The temperature-dependence of photosynthesis and respiration was fitted to empirical models to obtain maximum metabolic rates and thermal optima. The thermal optimum (Topt) for gross photosynthesis of Z. muelleri, which is more commonly distributed in sub-tropical to temperate regions, was 31°C. The Topt for photosynthesis of the tropical species, H. uninervis and C. serrulata, was considerably higher (35°C on average). This suggests that seagrass species are adapted to water temperature within their distributional range; however, when comparing among latitudes and seasons, thermal optima within a species showed limited acclimation to ambient water temperature (Topt varied by 1°C in C. serrulata and 2°C in H. uninervis, and the variation did not follow changes in ambient water temperature). The Topt for gross photosynthesis were higher than Topt calculated from plant net productivity, which includes above- and below-ground respiration for Z. muelleri (24°C) and H. uninervis (33°C), but remained unchanged at 35°C in C. serrulata. Both estimated plant net productivity and Topt are sensitive to the proportion of below-ground biomass, highlighting the need for consideration of below- to above-ground biomass ratios when applying thermal optima to other meadows. The thermal optimum for plant net productivity was lower than ambient summer water temperature in Z. muelleri, indicating likely contemporary heat stress. In contrast, thermal optima of H. uninervis and C. serrulata exceeded ambient water temperature. This study found limited capacity to acclimate: thus the thermal optima can forewarn of both the present and future vulnerability to ocean warming during periods of elevated water temperature.
- Published
- 2017
- Full Text
- View/download PDF
36. Influence of atmospheric conditions on surface salinity and sea temperature in the Adriatic in September for the period from 2010. to 2019
- Author
-
Sršen, Daria and Matić, Frano
- Subjects
PRIRODNE ZNANOSTI. Interdisciplinarne prirodne znanosti ,Adriatic Sea ,climate changes ,salinitet ,morske struje ,precipitation ,NATURAL SCIENCES. Interdisciplinary Natural Sciences ,salinity ,klimatske promjene ,sea temperature ,oborine ,Jadransko more ,temperatura mora ,sea currents ,višegodišnja varijabilnost ,multi-year variabilty - Abstract
U ovom radu analiziran je utjecaj atmosferskih čimbenika (temperature zraka i oborine) na temperaturu mora i salinitet te strujanje u Jadranskom moru za mjesec rujan u razdoblju od 2010. do 2019. godine. Prikazana je višegodišnja varijabilnost prostorne raspodjele temperature mora i saliniteta na dubini od 5 m, te strujanja na 5 i 20 m dubine. Podatci saliniteta i temperature na 5 m dubine dobiveni su višegodišnjim terenskim uzorkovanjem korištenjem CTD sonde, polja struja su produkt numeričke reanalize Copernicus programa, dok su podatci o temperaturi zraka i oborina rezultat klimatološke analize mjerenja na postajama Državnog hidrometeorološkog zavoda. Za promatrano razdoblje uočena je iznimna višegodišnja varijabilnost srednje temperature zraka i količine oborina te površinske temperature. Osim atmosferskih čimbenika na svojstva Jadranskog mora je utjecalo i Sredozemno more kroz komunikaciju preko Otrantskih vrata. U promatranom razdoblju zabilježen je porast saliniteta što je rezultiralo rekordnim vrijednostima saliniteta koje su bile veće od ranije izmjerenih. In this paper, the influence of atmospheric factors (air temperature and precipitation) on sea temperature and salinity and currents in the Adriatic Sea is analyzed for the month of September in the period from 2010 to 2019. Long-term variability of the spatial distribution of sea temperature and salinity at 5 m depth and currents at 5 and 20 m depth is presented. The data on salinity and temperature at 5 m depth were obtained by multi-year field sampling with CTD probes, the current fields are the product of numerical reanalysis of the Copernicus program, while the data on air temperature and precipitation are the result of climatological analysis of measurements at Croatian meteorological and hydrological service stations. Exceptional multiyear variability in the mean air temperature and precipitation, as well as in the surface temperature, was found for the observed period. In addition to atmospheric factors, the characteristics of the Adriatic Sea were also influenced by the Mediterranean Sea through the Strait of Otranto. An increase in salinity was observed during the observed period, leading to record salinity values, higher than those previously measured.
- Published
- 2022
37. Variations in Short Wave Radiation and Ocean Temperature in the Tropical Indian Ocean
- Author
-
Tomi Ilham Pahlewi, Ahmad Fadlan, Mohammad Ridwan Nur Prasetyo, Fajar Masan Bali, Imelda Umiyatul Badriyah, Muchammad Rizki, and Muhammad Aldi Lukman
- Subjects
Sea surface temperature ,Indian ocean ,Sea temperature ,Lag time ,Buoy ,Short wave radiation ,Organic Chemistry ,Environmental science ,East indian ,Indian Ocean Dipole ,Atmospheric sciences ,Biochemistry - Abstract
The purpose of this study was to know the results of the relation between short wave radiation (SWR) and sea temperature. This study used data of SWR and sea temperature from RAMA buoy which part of the data was obtained by the INA-PRIMA 2019. Besides, the SWR and Sea Temperature model data from ERA-5 and Copernicus were required to see these spatial and temporal variations. Diurnal analysis to determine the sea temperature responds to SWR parameters. While monthly analysis to see the variations of SWR and the sea temperature during Indian Ocean Dipole (IOD). The results show that there is a different response at sea temperature for each layer to the SWR parameter in diurnal. SWR can affect sea temperatures until 20 meters of depth. There is a time lag between 2 and 3 hours when the sun heats the sea until the sea surface temperature increases. The 20 meters of depth has a lag time until 4 hours. As for 40 to 80 meters of depth, the sea temperature was not longer responded by SWR, and the temperature is changed by the strength of these mixing.Warm pools are generally located in East Indian Ocean and the high SWR were very strong in West Indian Ocean along an anual.
- Published
- 2021
38. When cooling is worse than warming: investigations into the thermal tolerance of an endemic reef fish, Boopsoidea inornata
- Author
-
Cuen Muller, A-R Childs, W Froneman, C Allison, LA Bailey, and Warren M. Potts
- Subjects
Sea temperature ,Oceanography ,Fish physiology ,Coral reef fish ,Global warming ,Environmental science ,Upwelling ,Boopsoidea inornata ,Aquatic Science ,Laboratory experiment ,Ecology, Evolution, Behavior and Systematics - Abstract
Recent investigations suggest that global warming is likely to alter temperature regimes along the southeastern coastline of South Africa through the increased frequency of upwelling events. Identi...
- Published
- 2021
39. Projected effects of ocean warming on an iconic pelagic fish and its fishery
- Author
-
Francisco Alemany, Vicenç Moltó, Miquel Palmer, Mark Gatt, Andrés Ospina-Álvarez, Amina Besbes Benseddik, Ignacio Alberto Catalán, Sílvia Pérez-Mayol, Beatriz Morales-Nin, European Commission, Govern de les Illes Balears, and Ministerio de Economía y Competitividad (España)
- Subjects
0106 biological sciences ,010504 meteorology & atmospheric sciences ,Effects of global warming on oceans ,Science ,01 natural sciences ,Article ,Sea temperature ,Effects of global warming ,14. Life underwater ,0105 earth and related environmental sciences ,Coryphaena ,Multidisciplinary ,biology ,Ecology ,Phenology ,010604 marine biology & hydrobiology ,Pelagic zone ,biology.organism_classification ,Short life ,Fishery ,Environmental sciences ,Ocean sciences ,Productivity (ecology) ,13. Climate action ,Environmental science ,Medicine ,Climate sciences - Abstract
Increasing sea temperature is a driver of change for many fish traits, particularly for fast-growing epipelagic species with short life spans. With warming, altered spawning phenology and faster growth may produce substantially larger body sizes of the new cohort, affecting fishery productivity. We present an individual-based model (IBM) that predicts the distribution of fish length at catch under observed and projected thermal scenarios, accounting for mortality, temperature-dependent spawning phenology, temperature- and photoperiod- dependent growth. This IBM was demonstrated with Coryphaena hippurus (common dolphinfish), a circumglobally-distributed and highly thermophilic species sustaining commercial and recreational fisheries where it is present. The model projected a 13.2% increase in the average length at catch under marine heatwave conditions compared to the current thermal regime (1995–2005 average). Projections under RCP scenarios 4.5 and 8.5 by the end of the century led to 5.1% and 12.8% increase in average length, respectively. Furthermore, these thermal scenarios affected spawning phenology differently, producing higher variance in body size under RCP 8.5 scenario with respect to marine heatwave conditions. This study highlights how the environmental effects of climate change can alter the distribution of species length at catch., The present paper is part of the CERES project (H2020, EU 678193). Part of the data was obtained from the FAO-Copemed and FAO-Copemed II projects (http://www.faocopemed.org/). This study has been conducted using E.U. Copernicus Marine Service Information. V. Moltó acknowledges a predoctoral grant funded by the Regional Government of the Balearic Islands and the European Social Fund, A. Ospina Álvarez was supported by H2020 Marie Skłodowska-Curie Actions (746361), and S. Pérez-Mayol salary was founded by PN Project DREAMER (CTM2015-66676-C2-1-R). We also acknowledge Andreina Fenech, Marie Louise Pace, and Roberta Mifsud from the Department of Fisheries and Aquaculture of Malta for the data collection and provision.
- Published
- 2021
40. Record-breaking warming in the Kamchatka Current halocline
- Author
-
Natalia Shlyk and Konstantin Rogachev
- Subjects
geography ,geography.geographical_feature_category ,010504 meteorology & atmospheric sciences ,010505 oceanography ,Halocline ,Oceanography ,01 natural sciences ,Specific density ,Salinity ,Current (stream) ,Sea temperature ,Eddy ,Sea ice ,Geology ,Argo ,0105 earth and related environmental sciences - Abstract
We used historical CTD observations and Argo data to obtain the characteristics of the Kamchatka Current halocline and its eddies. Kamchatka Current eddies have a cold low salinity core in contrast with Aleutian eddies that contain warm and saline waters of Alaskan Stream origin. The Kamchatka Current eddies are smaller with diameter of ~ 100–120 km. Kamchatka Current eddies have a thick cold layer in a halocline. The temperature in their core increased by ~ 2.4 °C from the beginning of observations in 1990, while salinity decreased. We found that 2012 was the coldest year in the Kamchatka Current. Record-breaking warming occurred in the Kamchatka Current during 2015 to 2018. Temperature in the halocline rose by ~ 3 °C from 2012 to 2018 at 26.6σθ, while in the western Bering Sea temperature rose by 2.3 °C. It is plausible that the warming in the Kamchatka Current halocline during 2012 to 2018 is associated with the lowest recorded sea ice coverage in the Bering Sea. Similar warming occurred in the Oyashio Current. Salinity, temperature and specific density in the 2012 Simushir eddy were extremely low for the 30-year row of observations from 1990 to 2020. Extremely low salinity was also found in the 2012 Aleutian eddy off the Near Strait.
- Published
- 2021
41. Assessing the Speciation of a Cold Water Species, Japanese Sand Lance Ammodytes personatus, in the Northwestern Pacific by AFLP Markers
- Author
-
Zhiqiang Han, Zhiyong Wang, Tianxiang Gao, Takashi Yanagimoto, and Koji Iida
- Subjects
Ammodytes personatus ,climate change ,ocean current ,sea temperature ,Pleistocene glaciation isolation ,local adaptation ,isolation by distance ,Veterinary medicine ,SF600-1100 ,Zoology ,QL1-991 - Abstract
The use of molecular techniques in biodiversity research increasingly results in the recognition of multiple divergent mitochondrial DNA (mtDNA) lineages below the morphospecies level. However, the overlapping distribution of multiple divergent lineages raises the question of whether some of these lineages are in fact cryptic species. Assessing the status of these divergent lineages, delimiting evolutionarily significant units (ESUs), and identifying the dominant evolutionary and ecological drivers are critical components of successful wildlife conservation and management strategies. Amplified fragment length polymorphism (AFLP) markers were applied to characterize the phylogeography pattern of a cold water species, the Japanese sand lance Ammodytes personatus, in warm and cold ocean currents. A total of 211 individuals sampled from 12 populations through the species’ range, including samples from Kuroshio Current, Oyashio Current, Tsushima Current, and Yellow Sea, were analyzed. The Bayesian assignment probability test and Neighbor joining (NJ) analysis divided these populations into two genetically and geographically distinct clades (northern and southern clades) characterized by different sea surface temperatures. The incongruence between nuclear clades and previous mitochondrial lineages suggested that A. personatus is indeed composed of at least two genetically divergent cryptic species. Pleistocene glaciation isolation after secondary contact, local thermal adaptation, and isolation by distance may explain the observed geographic pattern of two cryptic species and genetic structure within clades.
- Published
- 2018
- Full Text
- View/download PDF
42. Sea temperature rise over the period 2002–2020 in Pelorus Sound, New Zealand – with possible implications for the aquaculture industry
- Author
-
David R. Plew, Matt H. Pinkerton, Niall Broekhuizen, and Mark. G. Gall
- Subjects
0106 biological sciences ,geography ,geography.geographical_feature_category ,Ecology ,Horizon (archaeology) ,010604 marine biology & hydrobiology ,Climate change ,010501 environmental sciences ,Aquatic Science ,01 natural sciences ,Sea temperature ,Oceanography ,Salmon farming ,Period (geology) ,Environmental science ,Pelorus ,Aquaculture industry ,Ecology, Evolution, Behavior and Systematics ,Sound (geography) ,0105 earth and related environmental sciences ,Water Science and Technology - Abstract
We assembled water-temperature data (1.0–15 m depth horizon) from several field studies (spanning 2003–2020) within Pelorus Sound to generate composite time-series of temperature at four locations....
- Published
- 2021
43. Os impactos da acidificação oceânica e elevação da temperatura do mar no ecossistema marinho / The impacts of the ocean acidification and rising sea temperature of the sea in the marine ecosystem
- Author
-
Maysa Maria Freitas dos Santos Souza, Lais Oliveira Ferreira, Anália Caroline Monteiro de Souza, and Edson de Figueiredo Gaudencio Barbosa
- Subjects
Sea temperature ,General Earth and Planetary Sciences ,Environmental science ,Marine ecosystem ,Ocean acidification ,Geomorphology ,General Environmental Science - Abstract
Os oceanos recebem o calor proveniente da atmosfera, e com o passar dos anos, o decorrente aquecimento das aguas, provocou lesoes as camadas abaixo da superficie aquatico. O desempenho do ecossistema aquatico mantem-se por meio da cadeia alimentar, onde a base e instituida por produtores primarios como fitoplâncton. Atraves de pesquisas bibliograficas em bancos de dados do Google academico e SciELO, tornou-se possivel essa revisao literaria. No passar dos anos os mares e oceanos comecaram a sofrer com o fenomeno chamado acidificacao que diminuicao do pH da agua do oceano devido ao dioxido de carbono liberado na atmosfera ocasionando um ambiente escassos a organismos calcificadores que colaborara com um possivel desequilibrio socioeconomico em diversas regioes do globo.
- Published
- 2021
44. Climate change impacts on wildlife in a High Arctic archipelago - Svalbard, Norway.
- Author
-
Descamps, Sébastien, Aars, Jon, Fuglei, Eva, Kovacs, Kit M., Lydersen, Christian, Pavlova, Olga, Pedersen, Åshild Ø., Ravolainen, Virve, and Strøm, Hallvard
- Subjects
- *
EFFECT of climate on wildlife resources , *MARINE ecology , *PHYSIOLOGICAL effects of global warming , *EFFECT of global warming on animals , *MARINE organisms , *SEA ice - Abstract
The Arctic is warming more rapidly than other region on the planet, and the northern Barents Sea, including the Svalbard Archipelago, is experiencing the fastest temperature increases within the circumpolar Arctic, along with the highest rate of sea ice loss. These physical changes are affecting a broad array of resident Arctic organisms as well as some migrants that occupy the region seasonally. Herein, evidence of climate change impacts on terrestrial and marine wildlife in Svalbard is reviewed, with a focus on bird and mammal species. In the terrestrial ecosystem, increased winter air temperatures and concomitant increases in the frequency of 'rain-on-snow' events are one of the most important facets of climate change with respect to impacts on flora and fauna. Winter rain creates ice that blocks access to food for herbivores and synchronizes the population dynamics of the herbivore-predator guild. In the marine ecosystem, increases in sea temperature and reductions in sea ice are influencing the entire food web. These changes are affecting the foraging and breeding ecology of most marine birds and mammals and are associated with an increase in abundance of several temperate fish, seabird and marine mammal species. Our review indicates that even though a few species are benefiting from a warming climate, most Arctic endemic species in Svalbard are experiencing negative consequences induced by the warming environment. Our review emphasizes the tight relationships between the marine and terrestrial ecosystems in this High Arctic archipelago. Detecting changes in trophic relationships within and between these ecosystems requires long-term (multidecadal) demographic, population- and ecosystem-based monitoring, the results of which are necessary to set appropriate conservation priorities in relation to climate warming. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
45. Semper’s (zoanthid) larvae: pelagic life, parentage and other problems
- Author
-
Ryland, J. S., de Putron, Samantha, Scheltema, R. S., Chimonides, P. J., Zhadan, D. G., Dumont, H. J., editor, Jones, M. B., editor, Azevedo, J. M. N., editor, Neto, A. I., editor, Costa, A. C., editor, and Martins, A. M. Frias, editor
- Published
- 2000
- Full Text
- View/download PDF
46. RETRACTED ARTICLE: Research on the relationship between seawater temperature changes and the start-up of characteristic towns in coastal cities based on spatial features
- Author
-
Xi, Jiaying and Bao, Honglin
- Published
- 2021
- Full Text
- View/download PDF
47. Intra-annual variability of the Western Mediterranean Oscillation (WeMO) and occurrence of extreme torrential precipitation in Catalonia (NE Iberia)
- Author
-
J. A. Lopez-Bustins, L. Arbiol-Roca, J. Martin-Vide, A. Barrera-Escoda, and M. Prohom
- Subjects
Mediterranean climate ,010504 meteorology & atmospheric sciences ,0208 environmental biotechnology ,Climate change ,02 engineering and technology ,01 natural sciences ,lcsh:TD1-1066 ,Sea temperature ,Clima mediterrani ,Canvi climàtic ,Precipitation ,lcsh:Environmental technology. Sanitary engineering ,lcsh:Environmental sciences ,0105 earth and related environmental sciences ,lcsh:GE1-350 ,Precipitacions (Meteorologia) ,lcsh:QE1-996.5 ,lcsh:Geography. Anthropology. Recreation ,Climatic change ,020801 environmental engineering ,lcsh:Geology ,Precipitations (Meteorology) ,Geography ,lcsh:G ,Climatology ,General Earth and Planetary Sciences - Abstract
In previous studies the Western Mediterranean Oscillation index (WeMOi) at daily resolution has proven to constitute an effective tool for analysing the occurrence of episodes of torrential precipitation over eastern Spain. The western Mediterranean region is a very sensitive area, since climate change can enhance these weather extremes. In the present study we created a catalogue of the extreme torrential episodes (≥200 mm in 24 h) that took place in Catalonia (NE Iberia) during the 1951–2016 study period (66 years). We computed daily WeMOi values and constructed WeMOi calendars. Our principal result reveals the occurrence of 50 episodes (0.8 cases per year), mainly concentrated in the autumn. We confirmed a threshold of WeMOi ≤ −2 to define an extreme negative WeMO phase at daily resolution. Most of the 50 episodes (60 %) in the study area occurred on days presenting an extreme negative WeMOi value. Specifically, the most negative WeMOi values are detected in autumn, from 11 to 20 October, coinciding with the highest frequency of extreme torrential events. On comparing the subperiods, we observed a statistically significant decrease in WeMOi values in all months, particularly in late October and in November and December. No changes in the frequency of these extreme torrential episodes were observed between both subperiods. In contrast, a displacement of the extreme torrential episodes is detected from early to late autumn; this can be related to a statistically significant warming of sea temperature.
- Published
- 2020
48. Paleoecological and recent data show a steady temporal evolution of carbon dioxide and temperature
- Author
-
Costas A. Varotsos, Maria N. Efstathiou, and Yuri Mazei
- Subjects
Atmospheric Science ,Alkenone ,010504 meteorology & atmospheric sciences ,Global temperature ,biology ,Global warming ,010501 environmental sciences ,Plankton ,biology.organism_classification ,Atmospheric sciences ,01 natural sciences ,Pollution ,Foraminifera ,Sea surface temperature ,Sea temperature ,chemistry.chemical_compound ,chemistry ,Carbon dioxide ,Environmental science ,Waste Management and Disposal ,0105 earth and related environmental sciences - Abstract
There is much debate today about the role of carbon dioxide in global warming. In this study we examine the intrinsic dynamics of the temporal evolution of the carbon dioxide amount and temperature by analyzing instrumental measurements data and paleo-reconstructed data to see if this dynamics remains stable in terms of its internal properties. The paleoecological data were based on over 20,000 sea surface temperature point reconstructions obtained from ocean sediment cores using alkenone unsaturation indices, applying ratios of Mg/Ca in planktonic foraminifera, and based upon microfossil abundances. The results of the analysis of the instrumental data fluctuations in land-ocean temperature and carbon dioxide in the period March 1958–April 2017, showed that the long-term dynamics of the fluctuations of these two parameters exhibit persistent power-law type behavior. This type of behavior also emerges from the same analysis of the reconstructed global mean sea temperature and carbon dioxide amount fluctuations over the past 805 thousand years. In addition, the time series of both parameters are characterized by multifractality for time scales of less than 4 years. Consequently, the intrinsic properties of carbon dioxide and global temperature have not changed over the past nearly one million years.
- Published
- 2020
49. The Role of Decadal Kelvin Wave in the Western of Sumatra and Along the South Coast of Java using Frequency-Wavenumber 2D Spectral Analysis
- Author
-
Reno Arif Rachman, Fadli Syamsudin, Nining Sari Ningsih, and Hanah Khoirunnisa
- Subjects
Java ,Anomaly (natural sciences) ,Sea-surface height ,Oceanography ,sea surface height anomaly ,Kelvin wave ,symbols.namesake ,Sea temperature ,Climatology ,symbols ,Wavenumber ,frequency-wavenumber 2D spectral analysis ,Spectral analysis ,Trough (meteorology) ,computer ,decadal variability ,Geology ,computer.programming_language - Abstract
This study observed the decadal variability of the sea surface height anomaly (SSHA) and identified the decadal Kelvin wave propagation along west-Sumatra and south coast of Java. SSHA data and the vertical distribution of sea temperature for 64 years from HYCOM model resulted has already used in this research. There are several methods to identify the propagation of decadal Kelvin wave. These methods were low-pass filter by cut-off 1 and 8 years, visual analytic by using Hovmӧller diagram method, and frequency-wavenumber 2D spectral analysis to identify the Kelvin wave propagation and its period. The decadal Kelvin wave could be observed in west coast of Sumatra and along south coast of Java. There are three propagations of decadal Kelvin wave and their velocities were 1.029x10-3 m/s (1974 – 1976), 0.21 m/s (1985 – 1986), and 6.86x10-4 m/s for 1998 to 2001 trough west Sumatra and southern Java. The frequency-wavenumber 2D spectral analysis produced the improvement of Kelvin wave and it has the period of 7.25 years. The occurrence of the Kelvin wave has a relation to IOD index. The average of the IOD index when the decadal Kelvin wave was occurring must be the negative value, its value was a -0.21.
- Published
- 2020
- Full Text
- View/download PDF
50. Propagation of Thermohaline Anomalies and Their Predictive Potential along the Atlantic Water Pathway
- Author
-
Langehaug, H. R., Ortega, Pablo, Counillon, F., Matei, Daniela, Maroon, E., Keenlyside, N., Mignot, Juliette, Wang, Y., Swingedouw, Didier, Bethke, I., Yang, S., Danabasoglu, Gokhan, Bellucci, Alessio, Ruggieri, P., Nicolì, D., Årthun, M., Nansen Environmental and Remote Sensing Center [Bergen] (NERSC), Bjerknes Centre for Climate Research (BCCR), Department of Biological Sciences [Bergen] (BIO / UiB), University of Bergen (UiB)-University of Bergen (UiB), Barcelona Supercomputing Center - Centro Nacional de Supercomputacion (BSC - CNS), Geophysical Institute [Bergen] (GFI / BiU), University of Bergen (UiB), Max Planck Institute for Meteorology (MPI-M), Max-Planck-Gesellschaft, University of Wisconsin-Madison, Océan et variabilité du climat (VARCLIM), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Environnements et Paléoenvironnements OCéaniques (EPOC), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Danish Meteorological Institute (DMI), National Center for Atmospheric Research [Boulder] (NCAR), Centro Euro-Mediterraneo per i Cambiamenti Climatici [Bologna] (CMCC), Istituto di Scienze dell'Atmosfera e del Clima [Bologna] (ISAC), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), University of Bologna/Università di Bologna, European Project: 727852,Blue-Action(2016), Langehaug H.R., Ortega P., Counillon F., Matei D., Maroon E., Keenlyside N., Mignot J., Wang Y., Swingedouw D., Bethke I., Yang S., Danabasoglu G., Bellucci A., Ruggieri P., Nicoli D., Arthun M., and Barcelona Supercomputing Center
- Subjects
Sea temperature ,Atmospheric Science ,Enginyeria agroalimentària::Ciències de la terra i de la vida::Climatologia i meteorologia [Àrees temàtiques de la UPC] ,Ocean circulation ,[SDU]Sciences of the Universe [physics] ,Simulació per ordinador ,Arctic Ocean ,[SDU.STU]Sciences of the Universe [physics]/Earth Sciences ,Decadal variability ,Climate prediction - Abstract
We assess to what extent seven state-of-the-art dynamical prediction systems can retrospectively predict winter sea surface temperature (SST) in the subpolar North Atlantic and the Nordic seas in the period 1970–2005. We focus on the region where warm water flows poleward (i.e., the Atlantic water pathway to the Arctic) and on interannual-to-decadal time scales. Observational studies demonstrate predictability several years in advance in this region, but we find that SST skill is low with significant skill only at a lead time of 1–2 years. To better understand why the prediction systems have predictive skill or lack thereof, we assess the skill of the systems to reproduce a spatiotemporal SST pattern based on observations. The physical mechanism underlying this pattern is a propagation of oceanic anomalies from low to high latitudes along the major currents, the North Atlantic Current and the Norwegian Atlantic Current. We find that the prediction systems have difficulties in reproducing this pattern. To identify whether the misrepresentation is due to incorrect model physics, we assess the respective uninitialized historical simulations. These simulations also tend to misrepresent the spatiotemporal SST pattern, indicating that the physical mechanism is not properly simulated. However, the representation of the pattern is slightly degraded in the predictions compared to historical runs, which could be a result of initialization shocks and forecast drift effects. Ways to enhance predictions could include improved initialization and better simulation of poleward circulation of anomalies. This might require model resolutions in which flow over complex bathymetry and the physics of mesoscale ocean eddies and their interactions with the atmosphere are resolved. Significance Statement In this study, we find that dynamical prediction systems and their respective climate models struggle to realistically represent ocean surface temperature variability in the eastern subpolar North Atlantic and Nordic seas on interannual-to-decadal time scales. In previous studies, ocean advection is proposed as a key mechanism in propagating temperature anomalies along the Atlantic water pathway toward the Arctic Ocean. Our analysis suggests that the predicted temperature anomalies are not properly circulated to the north; this is a result of model errors that seems to be exacerbated by the effect of initialization shocks and forecast drift. Better climate predictions in the study region will thus require improving the initialization step, as well as enhancing process representation in the climate models. Acknowledgments. The research leading to these results has received funding from the Blue-Action Project (European Union’s Horizon 2020 research and innovation program, Grant 727852), the Trond Mohn Foundation with the project Bjerknes Climate Prediction Unit (BCPU, Grant BFS2018TMT01), the NordForsk under the Nordic Centre of Excellence (ARCPATH, 76654), and from the Bjerknes Centre with the project SKD MEDEVAC. The research leading to these results has also received funding from the German Federal Ministry of Education and Research (BMBF) through the JPI Climate/JPI Oceans NextG-Climate Science-ROADMAP (FKZ: 01LP2002A; DM and Norwegian Grant 316618/JPIC/JPIO-04; HRL and NK and ANR-19-JPOC-003; JM). PO was funded by the Spanish Ministry for the Economy, Industry and Competitiveness through the grant RYC-2017-22772. SY also receives financial support from the Danish National Center for Climate Research (NCKF). The National Center for Atmospheric Research is a major facility sponsored by the U.S. National Science Foundation (NSF) under Cooperative Agreement 1852977. EM is supported by the U.S. NSF Office of Polar Programs Grant 1737377. The prediction simulations using EC-EARTH anomaly initialization system were performed by SMHI on resources provided by the Swedish National Infrastructure for Computing (SNIC). Peer Reviewed "Article signat per 16 autors/es: H. R. Langehaug, P. Ortega, F. Counillon, D. Matei, E. Maroon, N. Keenlyside, J. Mignot, Y. Wang, D. Swingedouw, I. Bethke, S. Yang, G. Danabasoglu, A. Bellucci, P. Ruggieri, D. Nicolì, and M. Årthun"
- Published
- 2022
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.