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Title: Tracking changing water budgets across the Bahamian archipelago
Freshwater resources on small island nations are already at risk from sea level rise and groundwater pumping however, increasing aridity due to climate change further stresses water availability. The amount of freshwater availability on small island nations is delicately balanced by incoming precipitation (P) and outgoing evapo- transpiration (ET). As climate changes, some island nations may see increasing aridity (ET > P) which can have implications for long term freshwater sustainability. Understanding how P and ET are changing allows small island nations to make more informed planning decisions regarding sustainable management and to adapt contemporary strategies to accommodate future change. The Bahamas is one such nation made up of over 700 small islands, many of which rely on freshwater lenses for potable water and irrigation. We use precipitation obtained from the TerraClimate reanalysis dataset and satellite derived actual evapotranspiration (ETa) to analyze how seasonal and yearly water budgets have changed over the last 16 years. We show that ETa is increasing across the Bahamas at a higher rate than global averages. The cause of ETa increases is driven by both increases in temperature and water availability form shifting precipitation patterns, ultimately driving decreases in the amount of available water to recharge the freshwater lens.  more » « less
Award ID(s):
1930451
PAR ID:
10555106
Author(s) / Creator(s):
; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Journal of Hydrology
Volume:
598
Issue:
C
ISSN:
0022-1694
Page Range / eLocation ID:
126178
Subject(s) / Keyword(s):
Carbonate Island Hydrology Freshwater lens Remote sensing Water budgets Reanalysis data
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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