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1. South America is becoming warmer, drier, and more flammable

Author

Sarah Feron, Raúl R. Cordero, Alessandro Damiani, Shelley MacDonell, Jaime Pizarro, Katerina Goubanova, Raúl Valenzuela, Chenghao Wang, Lena Rester, and Anne Beaulieu

Subjects
Geology, QE1-996.5, Environmental sciences, GE1-350
Abstract

Abstract South America is experiencing severe impacts from climate change. Although the warming of the subcontinent closely follows the global path, the rise of temperatures has been more pronounced in some regions, which have also seen a parallel increment in the occurrence of droughts and weather conditions associated with enhanced fire risk. Here, we use reanalysis datasets to analyze the progression of the concurring warm, dry, and high fire risk conditions (i.e., dry compounds) since 1971. We show that the frequency of these compound extremes has surged in key South American regions including the northern Amazon, which have seen a 3-fold increase in the number of days per year with extreme fire weather conditions (including high temperatures, dryness, and low humidity). Our results also suggest that the surface temperature of the tropical Pacific Ocean modulates the interannual variability of dry compounds in South America. While El Niño enhances the fire risk in the northern Amazon, dry extremes in the Gran Chaco region appear to be more responsive to La Niña.

Published
2024
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2. Response of the Black Sea Zooplankton to the Marine Heat Wave 2010: Case of the Sevastopol Bay

Author

Alexandra Gubanova, Katerina Goubanova, Olga Krivenko, Kremena Stefanova, Oksana Garbazey, Vladimir Belokopytov, Tatiana Liashko, and Elitsa Stefanova

Subjects
marine heat waves, mesozooplankton, copepod, crustacean, Sevastopol Bay, Black Sea, Naval architecture. Shipbuilding. Marine engineering, VM1-989, Oceanography, GC1-1581
Abstract

Global warming is increasing the frequency and severity of the marine heat waves, which poses a serious threat to the marine ecosystem. This study analyzes seasonal and interannual dynamics in the abundance and structure of the mesozooplankton community in Sevastopol Bay based on bi-monthly routine observations over 2003–2014. The focus is on the impact of the summer 2010 marine heat wave (MHW2010) on crustaceans belonging to different ecological groups. As a response to the MHW2010, three warm-water species (O. davisae, A. tonsa and P. avirostris) exhibiting the maximum seasonal density in latter summer showed a sharp increase in the annual abundance and their share in the mesozooplankton community. The increase in the annual abundance in 2010 of the eurythermal species P. parvus and P. polyphemoides exhibiting seasonal peaks in spring and autumn is not related to the MHW2010 but can be explained by a rise of temperature in the first part of the year. O. davisae and A. tonsa showed the most pronounced response among the species to the MHW2010, confirming that non-native species exhibited great flexibility as an adaptive response to environmental changes, especially in the case of climate warming. Among crustaceans observed in this study, O. davisae can be considered as an indicator of the environmental conditions associated with the warming of the Black Sea and the Mediterranean basin as a whole.

Published
2022
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3. Observed and Projected Hydroclimate Changes in the Andes

Author

José Daniel Pabón-Caicedo, Paola A. Arias, Andrea F. Carril, Jhan Carlo Espinoza, Lluís Fita Borrel, Katerina Goubanova, Waldo Lavado-Casimiro, Mariano Masiokas, Silvina Solman, and Ricardo Villalba

Subjects
hydroclimate of the Andes, global change in the Andes, hydroclimate trends in the Andes, hydroclimate projections of the Andes, climate change in the Andes, climate change scenarios for the Andes, Science
Abstract

The Andes is the most biodiverse region across the globe. In addition, some of the largest urban areas in South America are located within this region. Therefore, ecosystems and human population are affected by hydroclimate changes reported at global, regional and local scales. This paper summarizes progress of knowledge about long-term trends observed during the last two millennia over the entire Andes, with more detail for the period since the second half of the 20th century, and presents a synthesis of climate change projections by the end of the 21st century. In particular, this paper focuses on temperature, precipitation and surface runoff in the Andes. Changes in the Andean cryosphere are not included here since this particular topic is discussed in other paper in this Frontiers special issue, and elsewhere (e.g. IPCC,2019b). While previous works have reviewed the hydroclimate of South America and particular sectors (i.e., Amazon and La Plata basins, the Altiplano, Northern South America, etc.) this review includes for the first time the entire Andes region, considering all latitudinal ranges: tropical (North of 27°S), subtropical (27°S−37°S) and extratropical (South of 37°S). This paper provides a comprehensive view of past and recent changes, as well as available climate change projections, over the entire Andean range. From this review, the main knowledge gaps are highlighted and urgent research necessities in order to provide more mechanistic understanding of hydroclimate changes in the Andes and more confident projections of its possible changes in association with global climate change.

Published
2020
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5. Assessment of climate change impacts on precipitation and temperature over Subtropical Chile based on South America CORDEX-CORE regional simulations

Author

Limbert Torrez Rodriguez and Katerina Goubanova

Abstract

In this study, we analyze the projected changes in mean and extreme precipitation and temperature over subtropical Chile, based on simulations of 3 Regional Climate Models (RCMs) (RegCM4-7, REMO2015, and ETA) from South-America CORDEX-CORE, each one driven by three different CMIP5 GCMs. The RCM’s performance for the present climate is evaluated against the CR2MET (~5km) dataset.The changes for the end (2070-2099) of the century for the RCP8.5 scenario are assessed with respect to the historical period (1976-2005). Extreme events are expressed in terms of 30-yrs return values, estimated from the GEV distribution fitted to seasonal extremes for extended austral winter and summer.Accordingly, to GCMs projections, robust mean drying conditions are found among RCMs between 35ºS-40ºS in winter and 35ºS-45ºS in summer over the continental Chile and adjacent ocean. North of 30ºS REMO2015 and ETA show a statistically significant increase of mean winter precipitation over mountain regions. Another robust signal among the RCMs consists in an increase of extreme winter precipitation north of 35ºS over the mountain area. Increases in the maximum and minimum temperatures are significant over all domain for the 3 RCMs, but it is prominent to the north of 35°S (30°S) for REMO2015 and RegCM4-7 for winter (summer), especially over the mountain leeward, while ETA depicts the higher heating in the south of 30°S. The changes are mainly associated with a positive displacement of distribution (changes in location parameter) for temperatures and the amplification of interannual variability (positive changes in scale parameter) for precipitation. The physical processes responsible for these changes are discussed.

Published
2022
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6. Estimating the snow-rain transition zone in a semi-arid Andean catchment

Author

Shelley MacDonell, Katerina Goubanova, Simone Schauwecker, and Gabriel Palma

Subjects
Hydrology, geography, geography.geographical_feature_category, Transition zone, Drainage basin, Environmental science, Snow, Arid
Abstract

The height of the snow-rain transition during infrequent but high impact precipitation events, closely related to the 0⁰C-isotherm, is a crucial variable for snow cover extent, high discharge flows and flash floods in semi-arid northern Chile. Estimations of the snow-rain transition zone and its past and future changes are therefore fundamental for adaptation strategies and might eventually serve to develop early warning systems in this region. However, there are important challenges that hinder the assessment of the snow-rain transition zone in semi-arid environments and little is known about past and future changes under different global warming scenarios. For example, there are few radiosonde observations along the Andes and most weather stations are located in valley bottoms, influenced by local conditions and the assumption of free-air temperature lapse rates contributes to the uncertainty. We combine different data sets to estimate the past snow-rain transition zone of our study site, the semi-arid Elqui river catchment. Pictures of the snow line after precipitation events - available from social networks - are used to visually estimate the snow line elevation. These values are in high agreement with vertically extrapolated temperature from meteorological stations. Furthermore, we identified considerable biases between the extrapolated 0⁰C-isotherm from meteorological stations and ERA5 reanalysis data. These large biases are probably due to the lowering of the freezing level over complex terrain and need further analysis. Our results contribute to an improved understanding of the snow-rain transition in this region, but also serve to derive a climatology of this key variable along the Andes mountain range, needed for future projections.

Published
2021
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7. Observed and projected hydroclimate changes in the Andes

Author

Pabón-Caicedo, José Daniel, Arias, Paola A., Carril, Andrea F., Espinoza, J.C., Katerina, Goubanova, Lavado-Casimiro, W., Mariano, Masiokas, Silvina, Solman, and Ricardo, Villalba

Subjects
Hidrología, purl.org/pe-repo/ocde/ford#1.05.11 [https], Cambio Climático, Hidrometeorología, Escorrentía, Precipitación
Abstract

The Andes is the most biodiverse region across the globe. In addition, some of the largest urban areas in South America are located within this region. Therefore, ecosystems and human population are affected by hydroclimate changes reported at global, regional and local scales. This paper summarizes progress of knowledge about long-term trends observed during the last two millennia over the entire Andes, with more detail for the period since the second half of the 20th century, and presents a synthesis of climate change projections by the end of the 21st century. In particular, this paper focuses on temperature, precipitation and surface runoff in the Andes. Changes in the Andean cryosphere are not included here since this particular topic is discussed in other paper in this Frontiers special issue, and elsewhere (e.g. IPCC, 2019b). While previous works have reviewed the hydroclimate of South America and particular sectors (i.e., Amazon and La Plata basins, the Altiplano, Northern South America, etc.) this review includes for the first time the entire Andes region, considering all latitudinal ranges: tropical (North of 27 S), subtropical (27 S37 S) and extratropical (South of 37 S). This paper provides a comprehensive view of past and recent changes, as well as available climate change projections, over the entire Andean range. From this review, the main knowledge gaps are highlighted and urgent research necessities in order to provide more mechanistic understanding of hydroclimate changes in the Andes and more confident projections of its possible changes in association with global climate change. Por pares

Published
2020

8. Respective roles of remote and local wind stress forcings in the development of warm SST errors in the South-Eastern Tropical Atlantic in a coupled high-resolution model

Author

Emilia Sanchez-Gomez, Katerina Goubanova, Claudia Frauen, and Aurore Voldoire

Subjects
Atmospheric Science, 010504 meteorology & atmospheric sciences, Mixed layer, Atmospheric circulation, Wind stress, Forcing (mathematics), Tropical Atlantic, 010502 geochemistry & geophysics, 01 natural sciences, Sea surface temperature, Climatology, Ekman transport, Upwelling, 0105 earth and related environmental sciences
Abstract

Processes involved in the development of the warm sea surface temperature (SST) bias in the Tropical South-Eastern Atlantic (SETA) in a high resolution (HR) version of the CNRM-CM model are evaluated based on full-field initialized seasonal hindcasts starting at 1 February of each year for 2000–2009. Whereas the initial SST growth is likely associated with local atmospheric forcing, its further development is due to remote oceanic processes. A mixed layer heat budget analysis in SETA indicates a spurious warm horizontal advection observed as far as south of 25°S that appears at the beginning of March. It is associated with an erroneous oceanic mean state at the equator resulting from the mean equatorial westerly wind bias. A sensitivity experiment with corrected wind stress over the equatorial region suggests that the remote forcing explains about 57% of the SETA SST bias in March–May. Comparison with a lower resolution (LR) version of the model reveals that in general similar processes are responsible for the SST bias in both models. A strong reduction of the bias in the HR model is observed only over the near-coastal Southern Benguela region due to a better representation of atmospheric and oceanic processes controlling the coastal upwelling. Overall, the results of the inter-comparison of the SETA SST bias evolution in different sensitivity experiments performed in this study can be interpreted in terms of the relative contributions of (erroneous) warm horizontal advection, associated with equatorial forcing, and cold horizontal advection, associated with local offshore Ekman transport.

Published
2018
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9. Sensitivity of the near-shore oceanic circulation off central Chile to coastal wind profiles characteristics

Author

Marc Mallet, Orlando Astudillo, José A. Rutllant, Boris Dewitte, Frédéric Frappart, Marcel Ramos, Luis Bravo, and Katerina Goubanova

Subjects
Shore, geography, geography.geographical_feature_category, air sea land interactions, altimetry-derived surface wind, Oceanic circulation, Numerical modeling, coastal, Oceanography, wind drop-off, Geophysics, numerical modeling, Eastern Boundary Upwelling System, Space and Planetary Science, Geochemistry and Petrology, mesoscale processes, Earth and Planetary Sciences (miscellaneous), Environmental science, Sensitivity (control systems)
Abstract

In Eastern Boundary Upwelling Systems (EBUS), the upwelling favorable wind speeds decrease toward the coast in the so-called wind drop-off coastal strip, which has been shown to be influential on the coastal upwelling dynamics, particularly in terms of the relative contributions of Ekman drift and Ekman suction to coastal upwelling. Currently, the wind drop-off length scale is not properly resolved by the atmospheric forcing of regional ocean models in EBUS, featuring a smoother cross-shore wind profile that results in stronger near-shore speeds that could partly explain the coastal cold bias often found in those model simulations. Here, as a case study for the upwelling system off Central Chile, the sensitivity of upwelling dynamics to the coastal wind reduction is investigated using a Regional Ocean Modeling System (ROMS). Coastal wind profiles at different resolutions are first generated using a regional atmospheric model, validated from altimeter data, and then used to correct the coarse atmospheric wind forcing used for sensitivity experiments with ROMS. It is shown that the wind drop-off correction induces a reduction in the oceanic coastal jet intensity, a stronger poleward undercurrent and a coherent offshore Ekman drift. It also yields a significant reduction of the cold bias along the coast compared to the simulation with uncorrected winds. Such reduction cannot be solely explained by the reduced Ekman transport only partially compensated by increase in Ekman suction. The analysis of the surface heat budget reveals in fact that an important contributor to the cooling reduction along the coast in the presence of coastal wind drop-off is the heat flux term mediated by the reduction in the mixed-layer depth. Overall, our results illustrate the nonlinear response of the upwelling dynamics to the coastal wind profiles in this region.

Published
2019

10. Genesis dynamics of the Angola-Benguela Frontal Zone

Author

Hervé Giordani, Katerina Goubanova, and Shunya Koseki

Subjects
Intrusion, Frontogenesis, 010505 oceanography, Diagnostic analysis, Climatology, Confluence, Warm water, Stratification (water), Zonal and meridional, 01 natural sciences, Seasonal cycle, Geology, 0105 earth and related environmental sciences
Abstract

A diagnostic analysis of the climatological annual mean and seasonal cycle of the Angola Benguela Frontal Zone (ABFZ) is performed applying an ocean frontogenesis function (OFGF) to the ocean mixing layer (OML). The OFGF reveals that meridional confluence and the vertical tilting terms are the most dominant contributors to the frontogenesis of the ABFZ. The ABFZ shows a well-pronounced semi-annual cycle with two maximum (minimum) peaks in April–May and November–December (February–March and July–August). The development of the two maxima of frontogenesis is due to two different physical processes: enhanced tilting form March to April and the meridional confluence from September to October, respectively. The strong meridional confluence in September–October is closely related to the seasonal southward intrusion of tropical warm water to the ABFZ that seems to be associated with the development of the Angola Dome northwestern of the ABFZ. The strong tilting effect from March to April is attributed to the meridional gradient of vertical velocities whose effect is amplified in this period due to increasing stratification and shallow OML depth. The proposed OFGF can be viewed as a tool to diagnose the performance of CGCMs that generally fail in simulating realistically the position of the ABFZ, which leads to huge warm biases in the southeastern Atlantic.

Published
2018
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12. Surface winds off peru-chile: observing closer to the coast from radar altimetry

Author

Katerina Goubanova, Orlando Astudillo, Serena Illig, José A. Rutllant, Frédéric Frappart, Luis Bravo, M. Mallet, Marcel Ramos, and Boris Dewitte

Subjects
Coastal surface winds, 010504 meteorology & atmospheric sciences, 010505 oceanography, Atmospheric circulation, Mesoscale meteorology, Soil Science, Wind stress, Geology, Scatterometer, Wind drop-off, 01 natural sciences, Sea surface temperature, Climatology, Ekman transport, Upwelling, Environmental science, Satellite altimetry, Altimeter, Computers in Earth Sciences, Peru-Chile upwelling system, 0105 earth and related environmental sciences, Remote sensing
Abstract

The near-shore surface mesoscale atmospheric circulation in the upwelling systems off Peru and Chile is influential on the Sea Surface Temperature through Ekman transport and pumping. There has been a debate whether or not the so-called “wind drop-off”, that is a shoreward decrease of the surface wind speed near the coast, can act as an effective forcing of upwelling through Ekman pumping. Although the wind drop-off has been simulated by high-resolution atmospheric models, it has not been well documented due to uncertainties in the scatterometry-derived wind estimates associated with land contamination. Here we use the along-track altimetry-derived surface wind speed data from ENVISAT, Jason-1, Jason-2, and SARAL satellites, to document the spatial variability of the mean wind drop-off near the coast as estimated from the inversion of the radar backscattering coefficient. The data are first calibrated so as to fit with the scatterometer observations of previous and current satellite missions (QuikSCAT, ASCAT). The calibrated data are then analyzed near the coast and a wind drop-off scale is estimated. The results indicate that the wind drop-off takes place all along the coast, though with a significant alongshore variability in its magnitude. Differences between products are shown to be related both to the differences in repeat cycle between the different altimetry missions and to the peculiarities of the coastline shape at the coastal latitudes of the incident tracks. The relative contribution of Ekman pumping and Ekman transport to the total transport is also estimated indicating a comparable contribution off Chile while transport associated to Ekman pumping is on average ~ 1.4 larger than Ekman transport off Peru. Despite the aliasing effect associated with the weak repetitivity of the satellite orbit and the high frequency variability of the winds in this region, the analysis suggests that the seasonal cycle of the surface winds near the coast could be resolved at least off Peru.

Published
2017

13. SST subseasonal variability in the central Benguela upwelling system as inferred from satellite observations (1999-2009)

Author

Boris Dewitte, Eric Machu, Serena Illig, Véronique Garçon, and Katerina Goubanova

Subjects
010504 meteorology & atmospheric sciences, 010505 oceanography, Wind stress, Empirical orthogonal functions, Forcing (mathematics), Oceanography, 01 natural sciences, Sea surface temperature, symbols.namesake, Geophysics, 13. Climate action, Space and Planetary Science, Geochemistry and Petrology, Climatology, Middle latitudes, Earth and Planetary Sciences (miscellaneous), symbols, Environmental science, Upwelling, 14. Life underwater, Antarctic oscillation, Kelvin wave, 0105 earth and related environmental sciences
Abstract

Subseasonal variability of Sea Surface Temperature (SST) in the central Benguela upwelling system is investigated using TMI satellite-derived data over the period 1999-2009. Spatial patterns and time-frequency characteristics of subseasonal variability are documented based on Empirical Orthogonal Functions (EOF) decomposition and wavelet analysis. Despite the land contamination of the TMI satellite data within approximately 100 km off the coast the first EOF of SST anomalies allows characterizing the coastal upwelling variability at the subseasonal scale. Two regimes of variability are evidenced: a submonthly (2-30 days) regime with a dominant 11 days oscillation and a lower frequency intraseasonal (30-90 days) regime with a dominant 61 days oscillation. Both regimes are modulated, to a large extent, by the local surface wind stress and are consistent with Ekman dynamics. The seasonality of the relationship between wind stress and SST for submonthly (intraseasonal) regime is characterized by a marked semiannual (annual) cycle, which is explained in terms of the impact of seasonal change of the upper ocean stratification on the vertical advection process. The wind-driven SST subseasonal variability is shown to be associated with eastward propagating disturbances in the midlatitudes corresponding to a wave number 4. The results also suggest an important role of the Antarctic Oscillation in modulating the intraseasonal wind-driven SST variability. The characteristics of the equatorial intraseasonal Kelvin waves are documented in order to discuss possible impact of remote oceanic forcing on SST variability along the coast in the Benguela upwelling system.

Published
2013
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14. Seasonal variability of the Ekman transport and pumping in the upwelling system off central-northern Chile (~ 30° S) based on a high-resolution atmospheric regional model (WRF)

Author

Boris Dewitte, Orlando Astudillo, Luis Bravo, Marcel Ramos, and Katerina Goubanova

Subjects
lcsh:GE1-350, 010504 meteorology & atmospheric sciences, 010505 oceanography, lcsh:Geography. Anthropology. Recreation, Wind stress, Orography, Atmospheric model, 01 natural sciences, Boundary current, Sea surface temperature, lcsh:G, Climatology, Wind shear, Ekman transport, Upwelling, Geology, lcsh:Environmental sciences, 0105 earth and related environmental sciences
Abstract

Two physical mechanisms can contribute to coastal upwelling in eastern boundary current systems: offshore Ekman transport due to the predominant alongshore wind stress and Ekman pumping due to the cyclonic wind stress curl, mainly caused by the abrupt decrease in wind stress (drop-off) in a cross-shore band of 100 km. This wind drop-off is thought to be an ubiquitous feature in coastal upwelling systems and to regulate the relative contribution of both mechanisms. It has been poorly studied along the central-northern Chile region because of the lack in wind measurements along the shoreline and of the relatively low resolution of the available atmospheric reanalysis. Here, the seasonal variability in Ekman transport, Ekman pumping and their relative contribution to total upwelling along the central-northern Chile region (∼ 30° S) is evaluated from a high-resolution atmospheric model simulation. As a first step, the simulation is validated from satellite observations, which indicates a realistic representation of the spatial and temporal variability of the wind along the coast by the model. The model outputs are then used to document the fine-scale structures in the wind stress and wind curl in relation to the topographic features along the coast (headlands and embayments). Both wind stress and wind curl had a clear seasonal variability with annual and semiannual components. Alongshore wind stress maximum peak occurred in spring, second increase was in fall and minimum in winter. When a threshold of −3 × 10−5 s−1 for the across-shore gradient of alongshore wind was considered to define the region from which the winds decrease toward the coast, the wind drop-off length scale varied between 8 and 45 km. The relative contribution of the coastal divergence and Ekman pumping to the vertical transport along the coast, considering the estimated wind drop-off length, indicated meridional alternation between both mechanisms, modulated by orography and the intricate coastline. Roughly, coastal divergence predominated in areas with low orography and headlands. Ekman pumping was higher in regions with high orography and the presence of embayments along the coast. In the study region, the vertical transport induced by coastal divergence and Ekman pumping represented 60 and 40 % of the total upwelling transport, respectively. The potential role of Ekman pumping on the spatial structure of sea surface temperature is also discussed.

Published
2015
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15. Extremes in temperature and precipitation around the Mediterranean basin in an ensemble of future climate scenario simulations

Author

Katerina Goubanova, Laurent Li, Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-École des Ponts ParisTech (ENPC)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)

Subjects
Mediterranean climate, Global and Planetary Change, Climate change, Oceanography, Atmospheric sciences, Mediterranean Basin, Geophysical fluid dynamics, [SDU]Sciences of the Universe [physics], Climatology, Generalized extreme value distribution, Spatial ecology, Environmental science, Earth Science, Climate model, Precipitation
Abstract

International audience; A variable-grid atmospheric general circulation model, the LMDZ, with a local zoom over the Mediterranean is used to investigate potential future changes in climate extremes around the Mediterranean basin. Changes in extremes of annual minimum and maximum temperature, winter and summer 24-h maximum precipitation are discussed under the IPCC-A2 emission scenario. Three time slices of 30 years are chosen to represent respectively the end of the 20th century, the middle and the end of the 21st century. The boundary conditions were taken from the outputs of three global coupled climate models: from the Institut Pierre-Simon Laplace (IPSL), Centre National de Recherches Météorologiques (CNRM) and Geophysical Fluid Dynamics Laboratory (GFDL). These three global scenarios were used to estimate uncertainties associated with climate models. Extreme events are expressed in terms of return values, estimated from a Generalized Extreme Value distribution fitted to annual or seasonal extremes. The changes in distribution of extremes are analyzed to elucidate the nature of the changes in extremes. Magnitudes and main spatial patterns of the changes in extremes show a quite good consistency among three global scenarios. Comparison between changes in the middle and at the end of the 21st century does not reveal any remarkable discontinuity in future climate evolution. The maximum of warming occurs over Northeastern Europe for annual minimum temperature and over South Europe for annual maximum temperature. Averaged over the region, increase in cold extremes exceeds that in warm extremes. Changes in temperature extremes are mostly associated with shift of whole distribution (location parameter change) and in addition, for cold extremes, with changes in interannual variability, measured by the scale parameter. Mean precipitation changes are characterized by strong reduction belt over the Mediterranean and South Europe in winter, spring and summer. Precipitation extremes increase in all seasons except summer. These changes are predominantly associated with changes in the scale, but also with changes in the position and shape of the distribution. In general terms, it is suggested that the Mediterranean basin will experience a warmer climate with less total precipitation but more intense precipitation events.

Published
2007
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16. 9. Las diversas facetas de El Niño y sus efectos en la costa del Perú

Author

R. Flores, Sara Purca, Ivonne Montes Torres, Véronique Garçon, Jhan Carlo Espinoza, Katerina Goubanova, Ken Takahashi, Aurélien Paulmier, Waldo Lavado, A. Montecinos, Serena Illig, Pedro Rau, Kobi Alberto Mosquera Vásquez, Boris Dewitte, David Labat, and Luc Bourrel

Abstract

En: El Peru frente al cambio climatico: Resultados de investigaciones franco-peruanas. Editora cientifica: Anne Gregoire, Capitulo 9, 2014, p. 125-140.

Published
2014
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17. Forcing mechanisms of intraseasonal SST variability off central Peru in 2000-2008

Author

Sara Purca, Katerina Goubanova, Serena Illig, Gildas Cambon, Boris Dewitte, Julien Boucharel, Carlos H. Romero, Florian Monetti, and Roberto Flores

Subjects
Mixed layer, Advection, Wind stress, Forcing (mathematics), Oceanography, Atmospheric sciences, Physics::Geophysics, symbols.namesake, Sea surface temperature, Geophysics, Space and Planetary Science, Geochemistry and Petrology, Downwelling, Climatology, Earth and Planetary Sciences (miscellaneous), symbols, Environmental science, Upwelling, Kelvin wave, Physics::Atmospheric and Oceanic Physics
Abstract

The Sea Surface Temperature (SST) intraseasonal variability (40-90 days) along the coast of Peru is commonly attributed to the efficient oceanic connection with the equatorial variability. Here we investigate the respective roles of local and remote equatorial forcing on the intraseasonal SST variability off central Peru (8 degrees S-16 degrees S) during the 2000-2008 period, based on the experimentation with a regional ocean model. We conduct model experiments with different open lateral boundary conditions and/or surface atmospheric forcing (i.e., climatological or not). Despite evidence of clear propagations of coastal trapped waves of equatorial origin and the comparable marked seasonal cycle in intraseasonal Kelvin wave activity and coastal SST variability (i.e., peak in Austral summer), this remote equatorial forcing only accounts for similar to 20% of the intraseasonal SST regime, which instead is mainly forced by the local winds and heat fluxes. A heat budget analysis further reveals that during the Austral summer, despite the weak along-shore upwelling (downwelling) favorable wind stress anomalies, significant cool (warm) SST anomalies along the coast are to a large extent driven by Ekman-induced advection. This is shown to be due to the shallow mixed layer that increases the efficiency by which wind stress anomalies relates to SST through advection. Diabatic processes also contribute to the SST intraseasonal regime, which tends to shorten the lag between peak SST and wind stress anomalies compared to what is predicted from an advective mixed-layer model.

Published
2014

18. Biomass Changes And Trophic Amplification Of Plankton In A Warmer Ocean

Author

Xabier Irigoien, Caleb Smith, Emanuela Clementi, Guillem Chust, Yuri Artioli, Eric Machu, Bettina A. Fach, Katerina Goubanova, Corinna Schrum, Jason Holt, Kostas Tsiaras, Marina Chifflet, Baris Salihoglu, Marco Zavatarelli, J. Icarus Allen, Dhanya Pushpadas, Briac Le Vu, Sarah Wakelin, Ute Daewel, Momme Butenschön, Laurent Bopp, George Petihakis, Véronique Garçon, Isabelle Dadou, Heather Cannaby, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), DYNBIO LEGOS, Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Echanges Côte-Large (ECOLA), 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)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Chust G., Allen J.I., Bopp L., Schrum C., Holt J., Tsiara K., Zavatarelli M., Chifflet M., Cannaby H., Dadou I., Daewel U., Wakelin S.L., Machu E., Pushpadas D., Butenschoen M., Artioli Y., Petihakis G., Smith C., Garcon V., Goubanova K., Le Vu B., Fach B. A., Salihoglu B., Clementi E., and Irigoien X.

Subjects
Food Chain, Climate Change, Oceans and Seas, Effects of global warming on oceans, sea warming, ecosystem model, Zooplankton, Phytoplankton, Animals, Environmental Chemistry, Biomass, 14. Life underwater, trophic amplification, Ecosystem, General Environmental Science, Trophic level, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Global and Planetary Change, Biomass (ecology), Ecology, food web, fungi, plankton, Temperature, Models, Theoretical, 15. Life on land, Food web, Sea surface temperature, Oceanography, 13. Climate action, foo web, Upwelling, Environmental science, trphic amplification, primary production
Abstract

1365-2486; Ocean warming can modify the ecophysiology and distribution of marine organisms, and relationships between species, with nonlinear interactions between ecosystem components potentially resulting in trophic amplification. Trophic amplification (or attenuation) describe the propagation of a hydroclimatic signal up the food web, causing magnification (or depression) of biomass values along one or more trophic pathways. We have employed 3-D coupled physical-biogeochemical models to explore ecosystem responses to climate change with a focus on trophic amplification. The response of phytoplankton and zooplankton to global climate-change projections, carried out with the IPSL Earth System Model by the end of the century, is analysed at global and regional basis, including European seas (NE Atlantic, Barents Sea, Baltic Sea, Black Sea, Bay of Biscay, Adriatic Sea, Aegean Sea) and the Eastern Boundary Upwelling System (Benguela). Results indicate that globally and in Atlantic Margin and North Sea, increased ocean stratification causes primary production and zooplankton biomass to decrease in response to a warming climate, whilst in the Barents, Baltic and Black Seas, primary production and zooplankton biomass increase. Projected warming characterised by an increase in sea surface temperature of 2.29 ± 0.05 ºC leads to a reduction in zooplankton and phytoplankton biomasses of 11% and 6%, respectively. This suggests negative amplification of climate driven modifications of trophic level biomass through bottom-up control, leading to a reduced capacity of oceans to regulate climate through the biological carbon pump. Simulations suggest negative amplification is the dominant response across 47% of the ocean surface and prevails in the tropical oceans; whilst positive trophic amplification prevails in the Arctic and Antarctic oceans. Trophic attenuation is projected in temperate seas. Uncertainties in ocean plankton projections, associated to the use of single global and regional models, imply the need for caution when extending these considerations into higher trophic levels. This article is protected by copyright. All rights reserved.

Published
2014
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19. Assessing the impact of downscaled winds on a regional ocean model simulation of the Humboldt system

Author

Vincent Echevin, Gildas Cambon, Serena Illig, Katerina Goubanova, Boris Dewitte, Patrick Marchesiello, Echanges Côte-Large (ECOLA), Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Couplage physique-biogéochimie-carbone (PHYBIOCAR), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-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)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-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)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-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)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS Paris), 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)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), and 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)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636))

Subjects
Atmospheric Science, 010504 meteorology & atmospheric sciences, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], [SDE.MCG]Environmental Sciences/Global Changes, Wind stress, [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], Forcing (mathematics), Oceanography, 01 natural sciences, purl.org/pe-repo/ocde/ford#1.05.00 [http], Computer Science (miscellaneous), High spatial resolution, 14. Life underwater, El Niño, Atmospheric forcing, 0105 earth and related environmental sciences, Statistical downscaling, purl.org/pe-repo/ocde/ford#1.05.09 [http], 010505 oceanography, Regional modeling, Geotechnical Engineering and Engineering Geology, Current (stream), La Niña, purl.org/pe-repo/ocde/ford#1.05.11 [http], 13. Climate action, Climatology, Environmental science, Upwelling, Regional ocean model, Peru-Chile upwelling system, Peru–Chile upwelling system, El Nino, Downscaling
Abstract

International audience; Simulating the oceanic circulation in Eastern Boundary Upwelling Systems (EBUS) is a challenging issue due to the paucity of wind stress products of a sufficiently high spatial resolution to simulate the observed upwelling dynamics. In this study, we present the results of regional simulations of the Humboldt current system (Peru and Chile coasts) to assess the value of a statistical downscaling model of surface forcing. Twin experiments that differ only from the momentum flux forcing are carried out over the 1992-2000 period that encompasses the major 1997/98 El Niño/La Niña event. It is shown that the mean biases of the oceanic circulation can be drastically reduced simply substituting the mean wind field of NCEP reanalysis by a higher resolution mean product (QuikSCAT). The statistical downscaling model improves further the simulations allowing more realistic intraseasonal and interannual coastal undercurrent variability, which is notoriously strong off Central Peru and Central Chile. Despite some limitations, our results suggest that the statistical approach may be useful to regional oceanic studies of present and future climates.

Published
2013
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20. Change in El Niño flavours over 1958-2008: Implications for the long-term trend of the upwelling off Peru

Author

Gildas Cambon, Sara Purca, Katerina Goubanova, Ken Takahashi, Abdelfettah Sifeddine, Dimitri Gutiérrez, Boris Dewitte, Luc Ortlieb, David Correa, Jorge Vazquez-Cuervo, Serena Illig, Echanges Côte-Large (ECOLA), Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Paléoclimats, proxies, processus (PALEOPROXUS), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-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)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-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)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-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)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS Paris), 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)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), and 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)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636))

Subjects
010504 meteorology & atmospheric sciences, Simple Ocean Data Assimilation, Peru Undercurrent, Wind stress, 02 engineering and technology, High Resolution, Humboldt Current, Oceanography, 01 natural sciences, Pacific Ocean (Tropical), Coastal Upwelling, Coastal Zones, Vertical Structures, Peru, Equatorial Kelvin Wave, Cooling Trends|El Niño Modoki, 020701 environmental engineering, El Nino-Southern Oscillation, Pacific Ocean (East), Regional Model, Atmospheric Pressure, Mesoscale Activity, purl.org/pe-repo/ocde/ford#1.05.11 [https], Climatology, Teleconnections, symbols, Kelvin Waves, Geology, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], Climate Change, [SDE.MCG]Environmental Sciences/Global Changes, 0207 environmental engineering, Southern Oscillation, Climate change, Nickel Compounds, Simple Ocean Data Assimilations, Reanalysis, [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], Wind Stress, symbols.namesake, Sea Surface Temperature, 14. Life underwater, 0105 earth and related environmental sciences, Long-Term Trend, Upwelling, SST Anomalies, Cooling Systems, Numerical Model, Gravity Waves, El Niño, 13. Climate action, El Nino Modoki, Thermocline, Kelvin wave, Teleconnection
Abstract

International audience; The tropical Pacific variability has experienced changes in its characteristics over the last decades. In particular, there is some evidence of an increased occurrence of El Niño events in the central Pacific (a.k.a. 'Central Pacific El Niño' (CP El Niño) or 'El Niño Modoki'), in contrast with the cold tongue or Eastern Pacific (EP) El Niño which develops in the eastern Pacific. Here we show that the different flavours of El Niño imply a contrasted Equatorial Kelvin Wave (EKW) characteristic and that their rectification on the mean upwelling condition off Peru through oceanic teleconnection is changed when the CP El Niño frequency of occurrence increases. The Simple Ocean Data Assimilation (SODA) reanalysis product is first used to document the seasonal evolution of the EKW during CP and EP El Niño. It is shown that the strong positive asymmetry of ENSO (El Niño Southern Oscillation) is mostly reflected into the EKW activity of the EP El Niño whereas during CP El Niño, the EKW is negatively skewed in the eastern Pacific. Along with slightly cooler conditions off Peru (shallow thermocline) during CP El Niño, this is favourable for the accumulation of cooler SST anomalies along the coast by the remotely forced coastal Kelvin wave. Such a process is observed in a high-resolution regional model of the Humboldt Current system using the SODA outputs as boundary conditions. In particular the model simulates a cooling trend of the SST off Peru although the wind stress forcing has no trend. The model is further used to document the vertical structure along the coast during the two types of El Niño. It is suggested that the increased occurrence of the CP El Niño may also lead to a reduction of mesoscale activity off Peru.

Published
2012
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21. ENSO regimes: Reinterpreting the canonical and Modoki El Niño

Author

Katerina Goubanova, Ken Takahashi, Aldo Montecinos, and Boris Dewitte

Subjects
010504 meteorology & atmospheric sciences, Multivariate ENSO index, Empirical orthogonal functions, 010502 geochemistry & geophysics, 01 natural sciences, Uncorrelated, Sea surface temperature, La Niña, Geophysics, El Niño Southern Oscillation, El Niño, 13. Climate action, Climatology, General Earth and Planetary Sciences, Geology, Pacific decadal oscillation, 0105 earth and related environmental sciences
Abstract

[1] We propose that the first two empirical orthogonal function (EOF) modes of tropical Pacific sea surface temperature (SST) anomalies do not describe different phenomena (i.e., El Nino-Southern Oscillation (ENSO) and “El Nino Modoki”) but rather the nonlinear evolution of ENSO. We introduce two new uncorrelated indices (E and C), based on the leading EOFs, that respectively account for extreme warm events in the eastern and cold/moderate warm events in the central equatorial Pacific, corresponding to regimes with different evolution. Recent trends in ENSO can be described as an increase in the central Pacific (C) variability that is associated with stronger cold events, as well as a reduction in the eastern Pacific (E) variability within the cold/moderate warm regime, consistent with model projections. However, little can be said observationally with respect to the extreme warm regime.

Published
2011
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22. Statistical downscaling of sea-surface wind over the Peru-Chile upwelling region: diagnosing the impact of climate change from the IPSL-CM4 model

Author

Boris Dewitte, Pascal Terray, Katerina Goubanova, Keiko Takahashi, Mathieu Vrac, Francis Codron, Vincent Echevin, Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Instituto del Mar del Peru (IMARPE), Couplage physique-biogéochimie-carbone (PHYBIOCAR), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS Paris), 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)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), 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)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-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)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Département des Géosciences - ENS Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École des Ponts ParisTech (ENPC)-École polytechnique (X)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Instituto Geofísico del Perú (IGP), Variabilité climatique tropicale et globale (VARCLIM), Extrèmes : Statistiques, Impacts et Régionalisation (ESTIMR), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-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)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-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)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-École des Ponts ParisTech (ENPC)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), and 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)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-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)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)

Subjects
0106 biological sciences, Atmospheric Science, 010504 meteorology & atmospheric sciences, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], [SDE.MCG]Environmental Sciences/Global Changes, Climate change, [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], Atmospheric sciences, 01 natural sciences, Peru, Marine ecosystem, 14. Life underwater, Chile, 0105 earth and related environmental sciences, Statistical downscaling, Upwelling, 010604 marine biology & hydrobiology, Ocean current, Global warming, Coastal wind, Statistical model, 13. Climate action, Climatology, Environmental science, Satellite, Downscaling
Abstract

International audience; The key aspect of the ocean circulation off Peru-Chile is the wind-driven upwelling of deep, cold, nutrient-rich waters that promote a rich marine ecosystem. It has been suggested that global warming may be associated with an intensification of upwelling-favorable winds. However, the lack of high-resolution long-term observations has been a limitation for a quantitative analysis of this process. In this study, we use a statistical downscaling method to assess the regional impact of climate change on the sea-surface wind over the Peru-Chile upwelling region as simulated by the global coupled general circulation model IPSL-CM4. Taking advantage of the high-resolution QuikSCAT wind product and of the NCEP reanalysis data, a statistical model based on multiple linear regressions is built for the daily mean meridional and zonal wind at 10 m for the period 2000-2008. The large-scale 10 m wind components and sea level pressure are used as regional circulation predictors. The skill of the downscaling method is assessed by comparing with the surface wind derived from the ERS satellite measurements, with in situ wind observations collected by ICOADS and through cross-validation. It is then applied to the outputs of the IPSL-CM4 model over stabilized periods of the pre-industrial, 2 × CO2 and 4 × CO2 IPCC climate scenarios. The results indicate that surface along-shore winds off central Chile (off central Peru) experience a significant intensification (weakening) during Austral winter (summer) in warmer climates. This is associated with a general decrease in intra-seasonal variability.

Published
2011
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23. Coastal cooling and increased productivity in the main upwelling zone off Peru since the mid-twentieth century

Author

Daniel Quispe, Sara Purca, Dimitri Gutiérrez, Gabriel Vargas, Renato Salvatteci, David B. Field, Ioanna Bouloubassi, Boris Dewitte, Michelle Graco, Federico Velazco, Laurence Méjanelle, Abdelfettah Sifeddine, Luc Ortlieb, Anne Lorre, and Katerina Goubanova

Subjects
0106 biological sciences, South Pacific High, Alkenone, 010504 meteorology & atmospheric sciences, 010604 marine biology & hydrobiology, Global warming, Climate change, 01 natural sciences, Sea surface temperature, Geophysics, Oceanography, 13. Climate action, ERA-40, Climatology, General Earth and Planetary Sciences, Environmental science, Upwelling, Pressure cell, 0105 earth and related environmental sciences
Abstract

[1] We reconstructed a high-resolution, alkenone-based sea surface temperature (SST) record spanning the last ca. 150 years, from a sediment core retrieved within the main upwelling zone off Peru. A conspicuous SST decline is evidenced since the 1950s despite interdecadal SST variability. Instrumental SST data and reanalysis of ECMWF ERA 40 winds suggest that the recent coastal cooling corresponds mainly to an intensification of alongshore winds and associated increase of upwelling in spring. Consistently, both proxy and instrumental data evidence increased productivity in phase with the SST cooling. Our data expand on previous reports on recent SST cooling in other Eastern Boundary upwelling systems and support scenarios that relate coastal upwelling intensification to global warming. Yet, further investigations are needed to assess the role of different mechanisms and forcings (enhanced local winds vs. spin-up of the South Pacific High Pressure cell).

Published
2011
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24. Modes of covariability between sea surface temperature and wind stress intraseasonal anomalies along the coast of Peru from satellite observations (2000-2008)

Author

Kobi Mosquera, Serena Illig, Sara Purca, Boris Dewitte, Ken Takahashi, Lionel Renault, Daria Gushchina, Katerina Goubanova, Echanges Côte-Large (ECOLA), Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Instituto Geofisico del Peru, Instituto Geofísico del Perú, Instituto del Mar del Peru (IMARPE), Mediterranean Institute for Advanced Studies, Faculty of Geography, Moscow State University, Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)

Subjects
Atmospheric Science, MADDEN-JULIAN OSCILLATION, 010504 meteorology & atmospheric sciences, Wind stress, 010502 geochemistry & geophysics, Oceanography, Atmospheric sciences, 01 natural sciences, LOW-LEVEL JET, Earth and Planetary Sciences (miscellaneous), Water Science and Technology, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, purl.org/pe-repo/ocde/ford#1.05.09 [http], Ekman pumping, Ecology, EDDIES, Forestry, Madden–Julian oscillation, WEST-COAST, PART I, VARIABILITY, Geophysics, Anticyclone, Teleconnections, Satellite data, Climatology, symbols, Geology, MIXED-LAYER, Baroclinity, Soil Science, Aquatic Science, MJO, purl.org/pe-repo/ocde/ford#1.05.00 [http], symbols.namesake, Geochemistry and Petrology, Ekman transport, 14. Life underwater, TROPICAL PACIFIC, 0105 earth and related environmental sciences, Earth-Surface Processes, Upwelling, Paleontology, SST, 1997-1998 EL-NINO, CLIMATE, Sea surface temperature, 13. Climate action, Space and Planetary Science, SUBTROPICAL SOUTH-AMERICA, Kelvin wave
Abstract

The Tropical Rainfall Measuring Mission Microwave Imager sea surface temperature (SST) and QuikSCAT wind stress satellite data are used to investigate the intraseasonal upwelling variability along the coat of Peru over the period 2000-2008. Two regions of peak variance correspond to the central Peru region (Pisco region, 15°S) and the northern Peru region (Piura region, 5°S). A covariance analysis reveals a significant coherency between winds and SST anomalies off Pisco, consistent with Ekman pumping and transport dynamics. The upwelling cell consists in a meridionally extended fringe of colder (warmer) water extending as far as 250 km from the coast at 15°S. In the Piura region, the intraseasonal covariability pattern is represented by two modes, one relevant to the direct Ekman dynamics and the other one associated with the remote forcing of intraseasonal oceanic Kelvin wave. Two regimes of variability are evidenced. A low-period regime (10-25 days) is the signature of Ekman transport/pumping dynamics and is remotely forced by the migratory atmospheric disturbances across the southeastern Pacific anticyclone. A high-period regime (35-60 day band) is associated with the combined forcing of oceanic equatorial Kelvin waves and migratory atmospheric disturbances in the midlatitudes. In particular, the modes of covariability exhibit a prominent ∼50 day period energy peak. It is shown that this period arises from the impact of the first two baroclinic modes Kelvin wave, with the second baroclinic mode Kelvin wave being more influential on the Piura region. Copyright 2011 by the American Geophysical Union.

Published
2011
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25. Relation between Large-Scale Circulation and European Winter Temperature: Does It Hold under Warmer Climate?

Author

Francis Codron, Laurent Li, Katerina Goubanova, Pascal Yiou, Echanges Côte-Large (ECOLA), Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École des Ponts ParisTech (ENPC)-École polytechnique (X)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Extrèmes : Statistiques, Impacts et Régionalisation (ESTIMR), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-École des Ponts ParisTech (ENPC)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), and 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)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-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)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Atmospheric Science, 010504 meteorology & atmospheric sciences, BLOCKING, Climate commitment, Climate change, ENSEMBLE, 010502 geochemistry & geophysics, 01 natural sciences, 7. Clean energy, STATISTICS, NORTH-ATLANTIC, EVENTS, Impact studies, 13. Climate action, Homogeneous, Greenhouse gas, Climatology, PRECIPITATION, Environmental science, Circulation (currency), Precipitation, Scale (map), 0105 earth and related environmental sciences, WEATHER REGIMES
Abstract

ISI Document Delivery No.: 628GA Times Cited: 3 Cited Reference Count: 32 Cited References: Berner J, 2007, J ATMOS SCI, V64, P117, DOI 10.1175/JAS3822.1 Boe J, 2006, J GEOPHYS RES-ATMOS, V111, DOI [10.1029/2005JD006889, 10.1029/JD006889] Cassou C, 2005, J CLIMATE, V18, P2805, DOI 10.1175/JCLI3506.1 Christiansen B, 2005, J ATMOS SCI, V62, P2528, DOI 10.1175/JAS3490.1 Corti S, 1999, NATURE, V398, P799 D'Andrea F, 1998, CLIM DYNAM, V14, P385, DOI 10.1007/s003820050230 Dufresne JL, 2002, GEOPHYS RES LETT, V29, DOI 10.1029/2001GL013777 EFRON B, 1993, STAT APPL PROBABILIT, V57 Goubanova K, 2007, GLOBAL PLANET CHANGE, V57, P27, DOI 10.1016/j.gloplacha.2006.11.012 Houghton J. T., 2001, CLIMATE CHANGE 2001 Hourdin F, 2006, CLIM DYNAM, V27, P787, DOI 10.1007/s00382-006-0158-0 Hurrell J. W., 2003, GEOPHYS MONOGR SER, V134, DOI [10.1029/GM134., DOI 10.1029/GM134] Huth R, 1999, CLIMATE RES, V13, P91, DOI 10.3354/cr013091 KIMOTO M, 1993, J ATMOS SCI, V50, P2645, DOI 10.1175/1520-0469(1993)0502.0.CO;2 LEGRAS B, 1985, J ATMOS SCI, V42, P433, DOI 10.1175/1520-0469(1985)0422.0.CO;2 Majda AJ, 2006, P NATL ACAD SCI USA, V103, P8309, DOI 10.1073/pnas.0602641103 MICHELANGELI PA, 1995, J ATMOS SCI, V52, P1237, DOI 10.1175/1520-0469(1995)0522.0.CO;2 Najac J, 2009, CLIM DYNAM, V32, P615, DOI 10.1007/s00382-008-0440-4 Palmer TN, 1999, J CLIMATE, V12, P575, DOI 10.1175/1520-0442(1999)0122.0.CO;2 Plaut G, 2001, CLIMATE RES, V17, P285, DOI 10.3354/cr017285 SanchezGomez E, 2005, GEOPHYS RES LETT, V32, DOI 10.1029/2005GL023990 Schubert S, 1998, INT J CLIMATOL, V18, P1419, DOI 10.1002/(SICI)1097-0088(19981115)18:133.3.CO;2-Q Solomon S, 2007, CLIMATE CHANGE 2007: THE PHYSICAL SCIENCE BASIS, P19 Stephenson DB, 2004, Q J ROY METEOR SOC, V130, P583, DOI 10.1256/qj.02.146 Tank AMGK, 2002, INT J CLIMATOL, V22, P1441, DOI 10.1002/joc.773 Tibaldi S., 1990, Tellus, Series A (Dynamic Meteorology and Oceanography), V42A, DOI 10.1034/j.1600-0870.1990.t01-2-00003.x Uppala SM, 2005, Q J ROY METEOR SOC, V131, P2961, DOI 10.1256/qj.04.176 VAUTARD R, 1990, MON WEATHER REV, V118, P2056, DOI 10.1175/1520-0493(1990)1182.0.CO;2 von Storch H., 2001, STAT ANAL CLIMATE RE Wilby R.L., 2004, GUIDELINES USE CLIMA Yiou P, 2008, NONLINEAR PROC GEOPH, V15, P365 Yiou P, 2004, GEOPHYS RES LETT, V31, DOI 10.1029/2003GL019119 Goubanova, K. Li, L. Yiou, P. Codron, F. 3 AMER METEOROLOGICAL SOC BOSTON J CLIMATE; The idea of using large-scale information to predict local climate variability is widely exploited in climate change impact studies as an alternative to computationally expensive high-resolution models. This approach implies the hypothesis that the statistical relationship between large-scale climate states and local variables defined for the present-day climate remains valid in the altered climate. In this paper, the concept of weather regimes is used to deduce a relationship between large-scale circulation and European winter temperature. The change in temperature with increased greenhouse gases is, however, not homogeneous among the individual regimes. As a result, the impact of the weather regimes on local temperature changes varies in the future, limiting its usefulness for refining temperature changes to the small scale.

Published
2010
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26. Weather regime dependence of extreme value statistics for summer temperature and precipitation

Author

Katerina Goubanova, Pascal Yiou, M. Nogaj, Z. X. Li, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), 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)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Extrèmes : Statistiques, Impacts et Régionalisation (ESTIMR), 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)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-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)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-École des Ponts ParisTech (ENPC)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Mécanique des Fluides, Energies et Environnement (EDF R&D MFEE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École des Ponts ParisTech (ENPC)-École polytechnique (X)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)

Subjects
010504 meteorology & atmospheric sciences, 0207 environmental engineering, Geopotential height, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, 02 engineering and technology, Atmospheric sciences, 01 natural sciences, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Precipitation, lcsh:Science, 020701 environmental engineering, Extreme value theory, Parametric equation, Robustness (economics), Cluster analysis, 0105 earth and related environmental sciences, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], lcsh:QC801-809, Climatic variables, lcsh:QC1-999, lcsh:Geophysics. Cosmic physics, 13. Climate action, Environmental science, lcsh:Q, Weather patterns, lcsh:Physics
Abstract

Extreme Value Theory (EVT) is a useful tool to describe the statistical properties of extreme events. Its underlying assumptions include some form of temporal stationarity in the data. Previous studies have been able to treat long-term trends in datasets, to obtain the time dependence of EVT parameters in a parametric form. Since there is also a dependence of surface temperature and precipitation to weather patterns obtained from pressure data, we determine the EVT parameters of those meteorological variables over France conditional to the occurrence of North Atlantic weather patterns in the summer. We use a clustering algorithm on geopotential height data over the North Atlantic to obtain those patterns. This approach refines the straightforward application of EVT on climate data by allowing us to assess the role of atmospheric variability on temperature and precipitation extreme parameters. This study also investigates the statistical robustness of this relation. Our results show how weather regimes can modulate the different behavior of mean climate variables and their extremes. Such a modulation can be very different for the mean and extreme precipitation.

Published
2008
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