Jayaka D. Campbell

A review of observed and projected changes in climate for the islands in the Caribbean

Resumen Los cambios climaticos observados y proyectados tienen implicaciones socioeconomicas importantes para las islas del Caribe. El objetivo de este articulo es presentar informacion esencial sobre el cambio climatico —basada en estudios previos, observaciones disponibles y simulaciones de modelos climaticos— a escalas espaciales relevantes para las islas caribenas. Se utilizan datos del modelo general de circulacion (GCM) incluidos en el Proyecto de Comparacion de Modelos Acoplados fase 3 (CMIP3), asi como del modelo climatico regional (RCM) del Centro Hadley del Reino Unido, para aportar tanto informacion actual como informacion basada en proyecciones sobre precipitaciones y temperatura en estados insulares especifcos. Se utilizan observaciones reticuladas de estaciones y datos satelitales para estudiar el clima del siglo XX y evaluar el desempeno de los modelos climaticos. Con un enfoque centrado en la precipitacion, tambien se analizan factores como la temperatura superficial del mar, la presion al nivel del mar y los vientos que influyen en las variaciones estacionales de la precipitacion. La media del ensamble del CMIP3 y el RCM captan satisfactoriamente las peculiaridades de la circulacion atmosferica de gran escala en la region, pero no asi el ciclo estacional bimodal caracteristico de la precipitacion. La aridez en epocas de lluvias prevista en escenarios de cambio climatico en la region se ha abordado en estudios previos, pero la magnitud de la variacion es muy incierta en las simulaciones tanto del GCM como del RCM. La disminucion proyectada es mayor al inicio de la temporada de lluvias y suprime la sequia del medio verano en el Caribe occidental. Las simulaciones del RCM muestran avances respecto del GCM, sobre todo por sus mejores representaciones de la extension territorial, pero su desempeno depende en gran medida de la conduccion del GCM. El presente estudio destaca la necesidad de contar con observaciones de alta resolucion y comparar simulaciones de modelos climaticos para entender a fondo el cambio climatico y su impacto en las pequenas islas del Caribe.

The Precis Caribbean Story: Lessons and Legacies

By the beginning of the current century, there was heightened recognition that the Caribbean is highly vulnerable to the effects of climate change. Yet, there was very little climate change science information for the region and at the scale of the small islands that make up most of the region. To fill the gap, a group of regional scientists representing three institutions and four territories (Barbados, Belize, Cuba, and Jamaica) initiated a project to provide dynamically downscaled climate change information for the Caribbean. The Providing Regional Climates for Impacts Studies (PRECIS)-Caribbean initiative was premised on a shared workload with goals to build regional capacity to provide climate change information for the region from within the region, to provide much needed climate information in the shortest possible time frame, and to create a platform for sharing the information as widely as possible. Ten years later offers the opportunity for retrospection and evaluation, particularly since a phas...

Characterization of Future Caribbean Rainfall and Temperature Extremes across Rainfall Zones

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

Future Caribbean Climates in a World of Rising Temperatures: The 1.5 vs 2.0 Dilemma

AbstractA 10-member ensemble from phase 5 of the Coupled Model Intercomparison Project (CMIP5) is used to analyze the Caribbean’s future climate when mean global surface air temperatures are 1.5°, 2.0°, and 2.5°C above preindustrial (1861–1900) values. The global warming targets are attained by the 2030s, 2050s, and 2070s respectively for RCP4.5. The Caribbean on average exhibits smaller mean surface air temperature increases than the globe, although there are parts of the region that are always warmer than the global warming targets. In comparison to the present (using a 1971–2000 baseline), the Caribbean domain is 0.5° to 1.5°C warmer at the 1.5°C target, 5%–10% wetter except for the northeast and southeast Caribbean, which are drier, and experiences increases in annual warm spells of more than 100 days. At the 2.0°C target, there is additional warming by 0.2°–1.0°C, a further extension of warm spells by up to 70 days, a shift to a predominantly drier region (5%–15% less than present day), and a greater...

State of the climate in 2012 - eScholarship

Special supplement to the Bulletin of the American Meteorological Society vol.94, No. 8, August 2013