Letter | Published:

Future freshwater stress for island populations

Nature Climate Change volume 6, pages 720725 (2016) | Download Citation

Abstract

Global climate models project large changes in the terrestrial water balance for many regions over this century in response to greenhouse gas emission1,2,3,4,5,6,7,8,9, but insufficient resolution precludes such knowledge for approximately 18 million people living on small islands scattered across the world ocean. By accounting for evaporative demand a posteriori at 80 island groups distributed among Earth’s major ocean basins, we reveal a robust yet spatially variable tendency towards increasing aridity at over 73% of island groups (16 million people) by mid-century. Although about half of the island groups are projected to experience increased rainfall—predominantly in the deep tropics—projected changes in evaporation are more uniform, shifting the global distribution of changes in island freshwater balance towards greater aridity. In many cases, the magnitude of projected drying is comparable to the amplitude of the estimated observed interannual variability, with important consequences for extreme events as well as mean climate. Future freshwater stress, including geographic and seasonal variability, has important implications for climate change adaptation scenarios for vulnerable human populations living on islands across the world ocean.

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

References

  1. 1.

    , , & A diagnostic study of future evaporation changes projected in CMIP5 climate models. Clim. Dynam. 42, 2745–2761 (2014).

  2. 2.

    & Twenty-first-century multimodel subtropical precipitation declines are mostly midlatitude shifts. J. Clim. 25, 4330–4347 (2012).

  3. 3.

    & Scaling potential evapotranspiration with greenhouse warming. J. Clim. 27, 1539–1558 (2014).

  4. 4.

    , , & Global warming and 21st century drying. Clim. Dynam. 43, 2607–2627 (2014).

  5. 5.

    , , , & Patterns of the seasonal response of tropical rainfall to global warming. Nature Geosci. 6, 357–361 (2013).

  6. 6.

    et al. Aerosol- and greenhouse gas-induced changes in summer rainfall and circulation in the Australasian region: a study using single-forcing climate simulations. Atmos. Chem. Phys. 12, 6377–6404 (2012).

  7. 7.

    Increasing drought under global warming in observations and models. Nature Clim. Change 3, 52–58 (2013).

  8. 8.

    , , , & Accelerated dryland expansion under climate change. Nature Clim. Change 6, 166–171 (2016).

  9. 9.

    , , & Large rainfall changes consistently projected over substantial areas of tropical land. Nature Clim. Change 6, 177–181 (2016).

  10. 10.

    & GHG Inventories in PICCAP Countries: Evaluation and Regional Synthesis of National Greenhouse Gas Inventories: General Assessment and Regional Synthesis (South Pacific Regional Environment Programme, 2000).

  11. 11.

    Adapting to climate change in Pacific Island Countries: the problem of uncertainty. World Dev. 29, 977–993 (2001).

  12. 12.

    Climate Change 2014: Impacts, Adaptation, and Vulnerability (eds Barros, V. R. et al.) (Cambridge Univ. Press, 2014).

  13. 13.

    , & The hazards of indicators: insights from the environmental vulnerability index. Ann. Assoc. Am. Geogr. 98, 102–119 (2008).

  14. 14.

    , , & Global water resources: vulnerability from climate change and population growth. Science 289, 284–288 (2000).

  15. 15.

    United Nations Department of Economic and Social Affairs Population Division. World Population Prospects: The 2012 Revision Special Aggregates. ST/ESA/SER.A/335 (United Nations Department of Economic and Social Affairs Population Division, 2013).

  16. 16.

    & Sea-level rise and its impact on coastal zones. Science 328, 1517–1520 (2010).

  17. 17.

    & Four billion people facing severe water scarcity. Sci. Adv. 2, e1500323 (2016).

  18. 18.

    , & An overview of CMIP5 and the experiment design. Bull. Am. Meteorol. Soc. 93, 485–498 (2012).

  19. 19.

    , & The Coordinated Regional Downscaling Experiment: CORDEX; An International Downscaling Link to CMIP5 (International CLIVAR Project Office, 2011).

  20. 20.

    World Water Assessment Programme Water for People, Water for Life: A Joint Report by the Twenty Three UN Agencies Concerned with Freshwater (UNESCO, 2003).

  21. 21.

    Pacific Islands Forum Secretariat Pacific Cooperation Plan: Preliminary Sector Analysis for Water, Sanitation and Hygiene (South Pacific Applied Geoscience Commision, 2005);

  22. 22.

    , , & Aqueduct Country and River Basin Rankings: A Weighted Aggregation of Spatially Distinct Hydrological Indicators 28 (World Resources Institute, 2013).

  23. 23.

    United Nations Environment Programme (Edward Arnold, 1992).

  24. 24.

    et al. The Community Earth System Model: a framework for collaborative research. Bull. Am. Meteorol. Soc. 94, 1339–1360 (2013).

  25. 25.

    Natural evaporation from open water, hare soil and grass. Proc. R. Soc. Lond. A 193, 120–145 (1948).

  26. 26.

    Evaporation and surface-temperature. Q. J. R. Meteorol. Soc. 107, 1–27 (1981).

  27. 27.

    Evaporation and environment. Symp. Soc. Exp. Biol. 19, 205–234 (1964).

  28. 28.

    , & Little change in global drought over the past 60 years. Nature 491, 435–438 (2012).

  29. 29.

    et al. The ASCE Standardized Reference Evapotranspiration Equation (American Society of Civil Engineers, 2005).

  30. 30.

    & Robust responses of the hydrological cycle to global warming. J. Clim. 19, 5686–5699 (2006).

  31. 31.

    & Global warming and the weakening of the tropical circulation. J. Climate 20, 4316–4340 (2007).

  32. 32.

    , & Expansion of the Hadley cell under global warming. Geophys. Res. Lett. 34, L06805 (2007).

  33. 33.

    et al. The version-2 Global Precipitation Climatology Project (GPCP) monthly precipitation analysis (1979–present). J. Hydrometeorol. 4, 1147–1167 (2003).

  34. 34.

    et al. The NCEP/NCAR 40-year reanalysis project. Bull. Am. Meteorol. Soc. 77, 437–471 (1996).

  35. 35.

    & Global and regional scale precipitation patterns associated with the El-Niño Southern Oscillation. Mon. Weath. Rev. 115, 1606–1626 (1987).

  36. 36.

    Vulnerability of freshwater resources to climate change in the tropical Pacific region. Water Air Soil Pollut. 92, 203–213 (1996).

  37. 37.

    The ocean component of the global water cycle. Rev. Geophys. 33, 1395–1409 (1995).

  38. 38.

    , & Ocean salinities reveal strong global water cycle intensification during 1950 to 2000. Science 336, 455–458 (2012).

  39. 39.

    & Terrestrial aridity and its response to greenhouse warming across CMIP5 climate models. J. Clim. 28, 5583–5600 (2015).

  40. 40.

    & A global, self-consistent, hierarchical, high-resolution shoreline database. J. Geophys. Res. 101, 8741–8743 (1996).

  41. 41.

    et al. The ACCESS coupled model: description, control climate and evaluation. Aust. Meteorol. Oceanogr. 63, 41–64 (2013).

  42. 42.

    et al. An overview of BCC climate system model development and application for climate change studies. J. Meteorol. R. 28, 34–56 (2014).

  43. 43.

    et al. The CNRM-CM5.1 global climate model: description and basic evaluation. Clim. Dynam. 40, 2091–2121 (2013).

  44. 44.

    et al. The dynamical core, physical parameterizations, and basic simulation characteristics of the atmospheric component AM3 of the GFDL global coupled model CM3. J. Clim. 24, 3484–3519 (2011).

  45. 45.

    et al. GFDL’s ESM2 global coupled climate-carbon earth system models. Part II: carbon system formulation and baseline simulation characteristics. J. Clim. 26, 2247–2267 (2013).

  46. 46.

    et al. Present-day atmospheric simulations using GISS ModelE: Comparison to in situ, satellite, and reanalysis data. J. Clim. 19, 153–192 (2006).

  47. 47.

    et al. Development and evaluation of an Earth-System model-HadGEM2. Geosci. Model Dev. 4, 1051–1075 (2011).

  48. 48.

    , & Simulating present-day climate with the INMCM4.0 coupled model of the atmospheric and oceanic general circulations. Izv. Atmos. Ocean. Phys. 46, 414–431 (2010).

  49. 49.

    et al. Climate change projections using the IPSL-CM5 Earth System Model: from CMIP3 to CMIP5. Clim. Dynam. 40, 2123–2165 (2013).

  50. 50.

    et al. MIROC-ESM 2010: model description and basic results of CMIP5-20c3m experiments. Geosci. Model Dev. 4, 845–872 (2011).

  51. 51.

    et al. Improved climate simulation by MIROC5. Mean states, variability, and climate sensitivity. J. Clim. 23, 6312–6335 (2010).

  52. 52.

    et al. A new global climate model of the meteorological research institute: MRI-CGCM3-model description and basic performance. J. Meteorol. Soc. Jpn 90, 23–64 (2012).

Download references

Acknowledgements

K.B.K. and J.P.D. acknowledge support from the Strategic Environmental Research and Development Program (SERDP). SERDP is the environmental science and technology programme of the US Department of Defense (DoD) in partnership with the US Department of Energy (DOE) and the US Environmental Protection Agency (EPA). K.B.K. further acknowledges support from the Alfred P. Sloan Foundation and the James E. and Barbara V. Moltz Fellowship administered by the WHOI Ocean and Climate Change Institute (OCCI). K.J.A. acknowledges support from NSF grant BCS–1263609. The authors thank C. Ummenhofer for helpful discussions. The authors thank NOAA NCDC for providing GHCN station observations. The WHOI—Hawaii Ocean Timeseries Site (WHOTS) mooring is supported by NOAA through the Cooperative Institute for Climate and Ocean Research (CICOR) under Grant No. NA17RJ1223 and NA090AR4320129 to WHOI, and by NSF grants OCE–0327513, OCE–752606, and OCE–0926766 to the University of Hawaii.

Author information

Affiliations

  1. Cooperative Institute for Research in Environmental Sciences (CIRES), University of Colorado Boulder, 216 UCB, Boulder, Colorado 80309-0216, USA

    • Kristopher B. Karnauskas
  2. Department of Atmospheric and Oceanic Sciences, University of Colorado Boulder, 311 UCB, Boulder, Colorado 80309-0311, USA

    • Kristopher B. Karnauskas
  3. Department of Geology and Geophysics, Woods Hole Oceanographic Institution, 266 Woods Hole Road, Woods Hole, Massachusetts 02543-1050, USA

    • Jeffrey P. Donnelly
  4. School of Geography and Development, University of Arizona, PO Box 210137, Tucson, Arizona 85721, USA

    • Kevin J. Anchukaitis

Authors

  1. Search for Kristopher B. Karnauskas in:

  2. Search for Jeffrey P. Donnelly in:

  3. Search for Kevin J. Anchukaitis in:

Contributions

K.B.K. designed the study with substantial contributions from J.P.D. and K.J.A., K.B.K. analysed the data, all authors discussed and interpreted the results, K.B.K. wrote the initial draft of the manuscript, and all authors discussed and interpreted the results and edited the manuscript.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Kristopher B. Karnauskas.

Supplementary information

PDF files

  1. 1.

    Supplementary Information

    Supplementary Information

About this article

Publication history

Received

Accepted

Published

DOI

https://doi.org/10.1038/nclimate2987

Further reading