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There is a dearth of studies characterizing historical sea level variability at the local scale for the islands in the Caribbean. This is due to the lack of reliable long term tide gauge data. There is, however, a significant need for such studies given that small islands are under increasing threat from rising sea levels, storm surges, and coastal flooding due to global warming. The growing length of satellite altimetry records provides a useful alternative to undertake sea level analyses. Altimetry data, spanning 1993–2019, are used herein to explore multi-timescale sea level variability near the south coast of Jamaica, in the northwest Caribbean. Caribbean basin dynamics and largescale forcing mechanisms, which could account for the variability, are also investigated. The results show that the average annual amplitude off the south coast of Jamaica is approximately 10 cm with a seasonal peak during the summer (July–August). The highest annual sea levels occur within the Caribbean storm season, adding to the annual risk. The annual trend over the 27 years is 3.3 ± 0.4 mm/yr when adjusted for Glacial Isostatic Adjustment (GIA), instrumental drift, and accounting for uncertainties. This is comparable to mean global sea level rise, but almost twice the prior estimates for the Caribbean which used altimetry data up to 2010. This suggests an accelerated rate of rise in the Caribbean over the last decade. Empirical Orthogonal Function (EOF) and correlation analyses show the long-term trend to be a basin-wide characteristic and linked to warming Caribbean sea surface temperatures (SSTs) over the period. When the altimetry data are detrended and deseasoned, the leading EOF mode has maximum loadings over the northwest Caribbean, including Jamaica, and exhibits interannual variability which correlates significantly with a tropical Pacific-tropical Atlantic SST gradient index, local wind strength, and the Caribbean Low Level Jet (CLLJ). Correlations with the El Niño Southern Oscillation (ENSO) in summer, seen in this and other studies, likely arise through the contribution of the ENSO to the SST gradient index and the ENSO's modulation of the CLLJ peak strength in July. The results demonstrate the usefulness of altimetry data for characterizing sea level risk on various timescales for small islands. They also suggest the potential for developing predictive models geared towards reducing those risks. [ABSTRACT FROM AUTHOR]

ABSTRACT The Statistical Downscaling Model ( SDSM) is used to investigate future projections of daily minimum and maximum temperature extremes for 45 stations and rainfall extremes for 39 stations across the Caribbean and neighbouring regions. Models show good skill in reproducing the monthly climatology of the mean daily temperatures and the frequencies of warm days, warm nights, cool days and cool nights between 1961 and 2001. Models for rainfall exhibit lower skill but generally capture the monthly climatology of mean daily rainfall and the spatial distribution of the mean annual maximum number of consecutive dry days ( CDD) and mean annual count of days with daily rainfall above 10 mm ( R10). Future projections suggest an increase (decrease) in warm (cool) days and nights by 2071-2099 under the A2 and B2 scenarios relative to 1961-1990. An increase in CDD is suggested for most stations except some eastern Caribbean stations and Bahamas. Decreases in RX1 (monthly maximum 1-day precipitation), R10 and R95p (annual total rainfall above the 95th percentile) are also suggested for some northern Caribbean locations and Belize under the A2 scenario, compared to a mixture of increases and decreases for the eastern Caribbean. Atmospheric predictors used in SDSM correlate well with known oceanic and atmospheric drivers of Caribbean climate, e.g. the Atlantic Multidecadal Oscillation ( AMO) on a seasonal timescale. Atlantic sea surface temperatures and the Caribbean low level jet appear to have significant influence on Caribbean temperature and rainfall extremes. [ABSTRACT FROM AUTHOR]

This study considers long-term precipitation and temperature variability across the Caribbean using two gridded data sets (CRU TS 3.21 and GPCCv5). We look at trends across four different regions (Northern, Eastern, Southern and Western), for three different seasons (May to July, August to October and November to April) and for three different periods (1901-2012, 1951-2012 and 1979-2012). There are no century-long trends in precipitation in either data set, although all regions (with the exception of the Northern Caribbean) show decade-long periods of wetter or drier conditions. The most significant of these is for the Southern Caribbean region which was wetter than the 1961-1990 average from 1940 to 1956 and then drier from 1957 to 1965. Temperature in contrast shows statistically significant warming everywhere for the periods 1901-2012, 1951-2012 and for over half the area during 1979-2012. Data availability is a limiting issue over much of the region and we also discuss the reliability of the series we use in the context of what is known to be available in the CRU TS 3.21 data set. More station data have been collected but have either not been fully digitized yet or not made freely available both within and beyond the region. [ABSTRACT FROM AUTHOR]

End-of-century changes in Caribbean climate extremes are derived from the Providing Regional Climate for Impact Studies (PRECIS) regional climate model (RCM) under the A2 and B2 emission scenarios across five rainfall zones. Trends in rainfall, maximum temperature, and minimum temperature extremes from the RCM are validated against meteorological stations over 1979–1989. The model displays greater skill at representing trends in consecutive wet days (CWD) and extreme rainfall (R95P) than consecutive dry days (CDD), wet days (R10), and maximum 5-day precipitation (RX5). Trends in warm nights, cool days, and warm days were generally well reproduced. Projections for 2071–2099 relative to 1961–1989 are obtained from the ECHAM5 driven RCM. Northern and eastern zones are projected to experience more intense rainfall under A2 and B2. There is less consensus across scenarios with respect to changes in the dry and wet spell lengths. However, there is indication that a drying trend may be manifest over zone 5 (Trinidad and northern Guyana). Changes in the extreme temperature indices generally suggest a warmer Caribbean towards the end of century across both scenarios with the strongest changes over zone 4 (eastern Caribbean). [ABSTRACT FROM AUTHOR]

This study investigates the sensitivity of the one-way nested PRECIS regional climate model (RCM) to domain size for the Caribbean region. Simulated regional rainfall patterns from experiments using three domains with horizontal resolution of 50 km are compared with ERA reanalysis and observed datasets to determine if there is an optimal RCM configuration with respect to domain size and the ability to reproduce important observed climate features in the Caribbean. Results are presented for the early wet season (May-July) and late wet season (August-October). There is a relative insensitivity to domain size for simulating some important features of the regional circulation and key rainfall characteristics e.g. the Caribbean low level jet and the mid summer drought (MSD). The downscaled precipitation has a systematically negative precipitation bias, even when the domain was extended to the African coast to better represent circulation associated with easterly waves and tropical cyclones. The implications for optimizing modelling efforts within resource-limited regions like the Caribbean are discussed especially in the context of the region's participation in global initiatives such as CORDEX. [ABSTRACT FROM AUTHOR]

ABSTRACT A workshop was held at the University of the West Indies, Jamaica, in May 2012 to build capacity in climate data rescue and to enhance knowledge about climate change in the Caribbean region. Scientists brought their daily observational surface temperature and precipitation data from weather stations for an assessment of quality and homogeneity and for the calculation of climate indices helpful for studying climate change in their region. This study presents the trends in daily and extreme temperature and precipitation indices in the Caribbean region for records spanning the 1961-2010 and 1986-2010 intervals. Overall, the results show a warming of the surface air temperature at land stations. In general, the indices based on minimum temperature show stronger warming trends than indices calculated from maximum temperature. The frequency of warm days, warm nights and extreme high temperatures has increased while fewer cool days, cool nights and extreme low temperatures were found for both periods. Changes in precipitation indices are less consistent and the trends are generally weak. Small positive trends were found in annual total precipitation, daily intensity, maximum number of consecutive dry days and heavy rainfall events particularly during the period 1986-2010. Correlations between indices and the Atlantic multidecadal oscillation ( AMO) index suggest that temperature variability and, to a lesser extent, precipitation extremes are related to the AMO signal of the North Atlantic surface sea temperatures: stronger associations are found in August and September for the temperature indices and in June and October for some of the precipitation indices. [ABSTRACT FROM AUTHOR]

By the beginning of the current century, there was heightened recognition that the Caribbean is highly vulnerable to the effects of climate change. Yet, there was very little climate change science information for the region and at the scale of the small islands that make up most of the region. To fill the gap, a group of regional scientists representing three institutions and four territories (Barbados, Belize, Cuba, and Jamaica) initiated a project to provide dynamically downscaled climate change information for the Caribbean. The Providing Regional Climates for Impacts Studies (PRECIS)-Caribbean initiative was premised on a shared workload with goals to build regional capacity to provide climate change information for the region from within the region, to provide much needed climate information in the shortest possible time frame, and to create a platform for sharing the information as widely as possible. Ten years later offers the opportunity for retrospection and evaluation, particularly since a phase 2 initiative is being formulated. By both accident and design, the legacies of the PRECIS-Caribbean initiative include i) the positioning of the Caribbean to pose and answer for itself some of the emerging second-generation climate change questions; ii) the emergence of a regional template for capacity building in the sciences through cooperation; iii) an expanded regional capacity to undertake climate science; and iv) a significant body of climate change and climate science knowledge relevant to and at the scale of the Caribbean region. [ABSTRACT FROM AUTHOR]

Under global warming the Caribbean is projected to be significantly drier by century's end during its primary rainy season from May to November. The PRECIS regional model is used to simulate the end-of-century (2071-2100) manifestation of the Caribbean Low Level Jet (CLLJ) under two Intergovernmental Panel on Climate Change (IPCC) global warming scenarios. The CLLJ is a feature of the Intra-American seas which during its July peak is dynamically linked to a brief mid-summer drying and interruption of the Caribbean rainy season. The regional model captures the CLLJ's present-day spatial and temporal characteristics reasonably well, simulating both the boreal winter (February) and summer (July) peaks. Under global warming there is an intensification of the CLLJ's core strength from May through November. The intensification is such that by October the CLLJ is of comparable core strength to its present-day peak in July. The persistence of the strong CLLJ beyond July and through November is linked to the perpetuation of a dry pattern in the Caribbean in the future. In contrast, the boreal winter manifestation of the CLLJ is largely unaltered in the future. Copyright © 2012 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

Caribbean economies, lifestyles, activities, practices and operational cycles are intricately linked to climate, making them vulnerable to its variations and/or changes. As examples, climate extremes impact agriculture, fisheries, health, tourism, water availability, recreation, and energy usage, among other things. There is however limited incorporation of climate information in the long term developmental plans and policies of the region. This is in part due to a knowledge deficit about climate change, it's likely manifestation in the region and the possible impact on Caribbean societies. In this paper, a review of the growing bank of knowledge about Caribbean climate science; variability and change is undertaken. Insight is offered into the basic science of climate change, past trends and future projections for Caribbean climate, and the possible implications for the region. In the end a case is made for a greater response to the threats posed by climate change on the basis of the sufficiency of our current knowledge of Caribbean climate science. A general profile of what the response may look like is also offered. [ABSTRACT FROM AUTHOR]

Scenarios of rainfall and temperature changes for the period 2071-2100 under the A2 and B2 Special Report on Emissions scenarios are examined using the Hadley Centre Providing Regional Climates for Impacts Studies regional climate model. The model simulates 'present-day' (1979-1990) rainfall and temperature climatologies reasonably well, capturing the characteristic bimodality of Caribbean rainfall and the boreal summer maximum and winter minimum temperatures. Seasonal spatial patterns are also reproduced, but rainfall amounts are underestimated over the northern Caribbean island masses, including Cuba, Jamaica, Hispaniola and Puerto Rico. Temperatures over the region are also overestimated by 1-3 °C. For the period 2071-2100, temperatures are projected to increase across the region by 1-4 °C for all months irrespective of the scenario. The rainfall response varies with season with one of the more robust changes being an intensification of a gradient pattern in November-January, in which the northern Caribbean (i.e. north of 22°N) gets wetter and the southern Caribbean gets drier. There is also a robust June-October drying signal. The results point to changes in the regional circulation patterns due to the human-induced climate change and warrants further investigation. Copyright © 2010 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

This article presents a study regarding the Caribbean Low Level Jet. It discusses that the Caribbean Low Level Jet is shown to be a real and dominant climatological feature of the early summer Caribbean climate, which manifests as an intensification in the trade winds in the western Caribbean basin. The study reveals the variability in the strength and zonal extent of the Caribbean Low Level Jet which can be related to zonal sea surface temperature gradients between the eastern equatorial Pacific and the north tropical and equatorial Atlantic.

There is an increasing need to develop bushfire monitoring and early warning systems for Jamaica and the Caribbean. However, there are few studies that examine fire variability for the region. In this study the MODIS C6 Fire Archive for 2001–2019 is used to characterize bushfire frequencies across Jamaica and to relate the variability to large-scale climate. Using additive mixed model and backward linear regression, the MODIS represents 80% and 73% of the local Jamaica Fire Brigade (JFB) data variability for 2010–2015, respectively. However, the MODIS values are smaller by a factor of approximately 30. The MODIS climatology over Jamaica reveals a primary peak in March and a secondary maximum in July, coinciding with months of minimum rainfall. A significant positive linear trend is observed for July-August bushfire events over 2001–2019 and represents 29% of the season's variability. Trends in all-island totals in other seasons or annually were not statistically significant. However, positive annual trends in Zone 2 (eastern Jamaica) are statistically significant and may support an indication that a drying trend is evolving over the east. Significant 5-year and 3.5-year periodicities are also evident for April–June and September–November variability, respectively. Southern Jamaica and particularly the parish of Clarendon, known for its climatological dryness, show the greatest fire frequencies. The study provides evidence of linkages between fire occurrences over Jamaica and oceanic and atmospheric variability over the Atlantic and Pacific. For example, all-island totals show relatively strong association with the Atlantic Multidecadal Oscillation. The study suggests that development of an early warning system for bushfire frequency that includes climate indices is possible and shows strong potential for fire predictions. [ABSTRACT FROM AUTHOR]

Six members of the Hadley Centre's Perturbed Physics Ensemble for the Quantifying Uncertainty in Model Predictions (QUMP) project are downscaled using the PRECIS (Providing Regional Climates for Impact Studies) RCM (Regional Climate Model). Climate scenarios at long-term temperature goals (LTTGs) of 1.5, 2.0, and 2.5 °C above pre-industrial warming levels are generated for the Caribbean and six sub-regions for annual and seasonal timescales. Under a high emissions scenario, the LTTGs are attained in the mid-2020s, end of the 2030s, and the early 2050s, respectively. At 1.5 °C, the region is slightly cooler than the globe, land areas warmer than ocean, and for the later months, the north is warmer than the south. The far western and southern Caribbean including the eastern Caribbean island chain dry at 1.5 °C (up to 50%). At 2.0 °C, the warming and drying intensify and there is a reversal of a wet tendency in parts of the north Caribbean. Drying in the rainfall season accounts for much of the annual change. There is limited further intensification of the region-wide drying at 2.5 °C. Changes in wind strength in the Caribbean low-level jet region may contribute to the patterns seen. There are implications for urgent and targeted adaptation planning in the Caribbean. [ABSTRACT FROM AUTHOR]