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Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This is Part II of a two-part review about climate and climate variability focused on the Eastern Tropical Pacific (ETP) and the Caribbean Sea (CS). Both parts are aimed at providing oceanographers, marine biologists, and other ocean scientists, a guiding base for ocean-atmosphere interaction processes affecting the CS, the ETP, and the waters of Isla del Coco. Isla del Coco National Park is a Costa Rican World Heritage site. Part I analyzed the mean fields for both basins and a larger region covering 25° S - 35° N, 20° W - 130° W. Here we focus on a smaller area (65° W - 95° W, 0° - 20° N), as a complement to Part 1. Incoming solar radiation and surface energy fluxes reveal the complex nature of the ETP and CS for convective activity and precipitation on seasonal and intraseasonal time scales. Both regions are relevant as sources of evaporation and the associated moisture transport processes. The American Monsoon System influences the climate and climate variability of the ETP and CS, however, the precise way systems affect regional precipitation and transport of moisture, within the Intra Americas Sea (IAS) are not clear. Although the Caribbean Low-Level Jet (CLLJ) is known to act as a conveyor belt for moisture transport, intraseasonal and seasonal modes of the CLLJ and their interactions with other IAS systems, have to be further investigated. Trans-isthmic jets, exert a variable seasonal wind stress force over the ocean surface co-generating regions of great marine productivity. Isolated convection, the seasonal migration of the Intertropical Convergence Zone, the hurricane season, the Mid-Summer Drought, the seasonal and intraseasonal behavior of low-level jets and their interactions with transients, and the southward incursion of cold fronts contribute to regional seasonal precipitation. Many large-scale systems, such as El Niño-Southern Oscillation, the Atlantic Multidecadal Oscillation and the Madden-Julian Oscillation (MJO, also influence the variability of precipitation by modulating regional features associated with convection and precipitation. Monthly tropical storm (TS) activity in the CS and ETP basins is restricted to the period May-November, with very few cases in December. The CS presents TS peak activity during August, as well as for the number of hurricanes and major hurricanes, in contrast to the ETP that shows the same features during September. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Climatología is the property of Revista de Climatologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Present climate of northwestern South America and the southern Isthmus is detailed in terms of major hydro-climatic controls, supported by evidence from station records, reanalysis data and satellite information. In this tropical region, precipitation is the principal hydro-climatological variable to display great variability. The primary objective is to view the controls that operate at intra-seasonal to inter-decadal time scales. This is a topographical complex region whose climate influences range in provenance from the South Atlantic to the Canadian Prairies, and from the North Atlantic to the Eastern Pacific. The situation is further complicated by interactions and feedbacks, in time and space, between these influences, which are interconnected over various scales. The greatest single control on the annual cycle is the meridional migration of the Inter-tropical Convergence Zone and its pattern of associated trade winds. Consideration of these alone and their interaction with the Cordilleras of the Andes and Central America produce a variety of unimodal and bimodal regimes. Regionally, two low level jet streams, the westerly Choco jet (5°N) and the easterly San Andrés jet (12–14°N), and their seasonal variability, have tremendous significance, as do mesoscale convective storms and mid-latitude cold fronts from both the northern (“nortes”) and southern (“friagems”) hemispheres. There are many examples of hydro-climatological feedbacks within the region. Of these the most notable is the interaction between evaporation over the Amazon, precipitation onto the eastern Andes and streamflow from the headwaters of the Amazon. This is further compounded by the high percentages of recycled precipitation over large areas of the tropics and the potential impacts of anthropogenic modification of the land surface. The El Niño-Southern Oscillation phenomenon (ENSO) is the greatest single cause of interannual variability within the region, yet its effects are not universal in their timing, sign or magnitude. A set of regional physical connections to ENSO are established and their varying local manifestations are viewed in the context of the dominant precipitation generating mechanisms and feedbacks at that location. In addition, some potential impacts of longer run variations within the ocean-atmosphere system of the Atlantic are examined independently and in conjunction with ENSO. This review of the climatic controls and feedbacks in the region provides a spatial and temporal framework within which the highly complex set of factors and their interactions may be interpreted from the past. [Copyright &y& Elsevier]