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

Climate change already challenges people's livelihood globally and it also affects plant health. Rising temperatures facilitate the introduction and establishment of unwanted organisms, including arthropods, pathogens, and weeds (hereafter collectively called pests). For example, a single, unusually warm winter under temperate climatic conditions may be sufficient to assist the establishment of invasive plant pests, which otherwise would not be able to establish. In addition, the increased market globalization and related transport of recent years, coupled with increased temperatures, has led to favorable conditions for pest movement, invasion, and establishment worldwide. Most published studies indicate that, in general, pest risk will increase in agricultural ecosystems under climate-change scenarios, especially in today's cooler arctic, boreal, temperate, and subtropical regions. This is also mostly true for forestry. Some pests have already expanded their host range or distribution, at least in part due to changes in climate. Examples of these pests, selected according to their relevance in different geographical areas, are summarized here. The main pathways used by them, directly and/or indirectly, are also discussed. Understanding these pathways can support decisions about mitigation and adaptation measures. The review concludes that preventive mitigation and adaptation measures, including biosecurity, are key to reducing the projected increases in pest risk in agriculture, horticulture, and forestry. Therefore, the sustainable management of pests is urgently needed. It requires holistic solutions, including effective phytosanitary regulations, globally coordinated diagnostic and surveillance systems, pest risk modeling and analysis, and preparedness for pro-active management. [ABSTRACT FROM AUTHOR]

Bushfire management which incorporates fire potential indices is still in its infancy in Jamaica and the Caribbean. In this study three bushfire potential indices—Keetch–Byram Drought Index (KBDI), Vapour Pressure Deficit (VPD) and Water Potential (Ψw)—are calculated for south-central Jamaica where bushfire frequencies are highest. The skills of the indices are evaluated using their representation of the normalised bushfire climatology, monthly and seasonal (December–March/DJFM; April–June/AMJ; July–August/JA and September–November/SON) fire variability for the periods 2013–2017, 2010–2019 and 2001–2019. Fire data are obtained from the MODIS C6 Archive and Jamaica Fire Brigade (JFB). The relationship between the fire indices and large-scale oceanic and atmospheric features are also examined. The results suggest that Ψw exhibits strong correlations with the MODIS and JFB climatologies and represents well the maxima in March and July and the local minima in May–June and October. Ψw and VPDI also show good hit rates for moderate and high-risk categories in south-central Jamaica (though with relatively high false alarm rates). Regression models premised on Ψw and VPD respectively show good skill in representing AMJ (R2 = 57–58%), SON (R2 = 57–58%) and JA (R2 = 57–60%) fire variability. Variability during DJFM is poorly captured by any fire index. Although the KBDI represents the normalised climatology reasonably well its peaks occur one month later, that is, in April and August. KBDI exhibits strong and statistically significant correlations with JFB and MODIS climatologies, but seasonal models premised on KBDI do not perform as well as for the other two indices except in JA. All indices had a statistically significant relationship on both monthly and 1 month lag time scales for NINO3 and TNA-NINO3 large-scale climate indices. The indices, and in particular Ψw, show good prospects for producing seasonal bushfire outlooks for south-central Jamaica and Jamaica in general. These results also suggest the usefulness of monitoring large-scale oceanic patterns as part of the monitoring framework for bushfires in the island. [ABSTRACT FROM AUTHOR]

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

The Caribbean, along with other small island developing states (SIDS), have advocated for restricting global warming to 1.5 °C above pre-industrial levels by the end of the current century. Solar radiation management (SRM) may be one way to achieve this goal. This paper examines the mean Caribbean climate under various scenarios of an SRM-altered versus an SRM-unaltered world for three global warming targets, namely, 1.5, 2.0 and 2.5 °C above pre-industrial levels. Data from the Geoengineering Model Intercomparison Project Phase 1 (GeoMIP1) were examined for two SRM scenarios: the G3 experiment where there is a gradual injection of sulfur dioxide (SO2) into the tropical lower stratosphere starting in 2020 and terminating after 50 years, and the G4 experiment where a fixed 5 Teragram (Tg) of SO2 per year is injected into the atmosphere starting in 2020 and ending after 50 years. The results show that SRM has the potential to delay attainment of the 1.5, 2.0 and 2.5 °C global warming targets. The extent of the delay varies depending on the SRM methodology but may be beyond mid-century for the 1.5 °C goal. In comparison, however, the higher temperature thresholds are both still attained before the end of century once SRM is ceased, raising questions about the value of the initial delay. The application of SRM also significantly alters mean Caribbean climate during the global warming target years (determined for a representative concentration pathway 4.5 (RCP4.5) world without SRM). The Caribbean is generally cooler but drier during the 1.5 °C years and similarly cool but less dry for years corresponding to the higher temperature targets. Finally, the mean Caribbean climate at 1.5 °C differs if the global warming target is achieved under SRM versus RCP4.5. The same is true for the higher warming targets. The implications of all the results are discussed as a background for determining whether SRM represents a viable consideration for Caribbean SIDS to achieve their "1.5 to stay alive" goal. [ABSTRACT FROM AUTHOR]

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

The existence of several gridded precipitation products (GPP) has facilitated studies related to climate change, climate modeling, as well as a better understanding of the physical processes underpinning this key variable. Due to complexities in estimating rainfall, gridded datasets exhibit different levels of accuracy across regions, even when they are developed at relatively high resolution or using sophisticated procedures. The performance of 16 GPP are evaluated over the Caribbean region, which includes the Caribbean Islands, and portions of Central South America. Monthly data for sixty weather stations are used as a reference for the period 1983–2010. The 16 GPP include six products based on station data only, two that combine ground station and satellite information, two merging station and reanalysis information, four based on reanalysis, and two using multisource information. The temporal resolution of the GPP ranged between daily and monthly and spatial resolution from 0.033° to 0.5°. The methodological approach employed combined a comparison of regional and sub-regional precipitation annual cycles, the Kling–Gupta efficiency (KGE) index, as well as several metrics derived from the standardized precipitation index (SPI). Overall, the best performances were obtained from GPCC025 and MSWEP2, likely reflecting the positive impact of the large number of station data utilized in their development. It is also demonstrated that a higher spatial resolution does not always mean better accuracy. There is a need for this kind of assessment when undertaking climate studies in regions like the Caribbean where resolution is a significant consideration. ERA5 performed best among the reanalyses analyzed and has the potential to be used to develop regionally based GPP by applying bias correction or downscaling techniques. The methodological approach employed provides a comprehensive and robust evaluation of the relative strengths and weaknesses of GPP in the Caribbean region. [ABSTRACT FROM AUTHOR]