Impacts of Climate Changes on the Caribbean Low Level Jet and the Mid-Summer Drought
Abstract
The Intra-Americas Region (IAR), home to over 80 million people, is sensitive to climate changes and contains fragile ecosystems. However, the mechanisms that drive the varying climate trends in the IAR have yet to be fully characterized. Previous research efforts have studied the drivers that potentially contribute to the complexity and variability of climate in this region. These efforts include the origins of the Mid-Summer Drought (MSD) and Bimodal Precipitation pattern, aerosol contributions (such as Saharan dust) to cloud formation and precipitation development in the area, sea surface temperature (SST) change and anomalies, vertical wind shear and its effects on precipitation variability, the influence of large-scale oscillation indices on early season Caribbean climate (e.g., ENSO, NAO), and the role of the Caribbean Low Level Jet (CLLJ), a 925-hPa zonal wind region, on modulating regional changes within the IAR. Furthermore, global warming impacts these mechanisms. According to the Intergovernmental Panel on Climate Change, Small Island Developing States located in the IAR are likely to be among the most seriously impacted regions on Earth by these global climate changes. It has also been shown that climate changes, as reflected in this region, not only have local impacts, but also are significantly linked to climate and weather conditions in North and South America and other areas surrounding the IAR. In order to understand the climate dynamics, and characterize its related drivers, historical climate trends in the IAR are investigated with an emphasis on the vertical structure components of the Planetary Boundary Layer. The goal is to identify the drivers and trends of the CLLJ due to the potential impact it has on the climate of the IAR. Based on previous studies correlations between the CLLJ, SSTs, moisture transport (dry/wet conditions), and vertical wind shear during peak hurricane season were obtained. However, these studies, in addition to others, have indicated that the dynamics of the CLLJ itself needs further investigation. The methodology used for the study presented here includes analysis of historical climate trends in the IAR using surface station data, large-scale vertical gridded atmospheric data, and SSTs datasets. This analysis leads to the characterization of the mechanisms involved in the CLLJ dynamic circulation, its influence on the MSD, and observed changes of key climatic variables.
- Publication:
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AGU Spring Meeting Abstracts
- Pub Date:
- May 2013
- Bibcode:
- 2013AGUSM.A33D..05G
- Keywords:
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- 3305 ATMOSPHERIC PROCESSES / Climate change and variability