The University of Southampton
University of Southampton Institutional Repository

Global assessment of trends in wetting and drying over land

Global assessment of trends in wetting and drying over land
Global assessment of trends in wetting and drying over land
Changes in the hydrological conditions of the land surface have substantial impacts on society1,2. Yet assessments of observed continental dryness trends yield contradicting results3-7. The concept that dry regions dry out further, whereas wet regions become wetter as the climate warms has been proposed as a simplified summary of expected8-10 as well as observed10-14 changes over land, although this concept is mostly based on oceanic data8,10. Here we present an analysis of more than 300 combinations of various hydrological data sets of historical land dryness changes covering the period from 1948 to 2005. Each combination of data sets is benchmarked against an empirical relationship between evaporation, precipitation and aridity. Those combinations that perform well are used for trend analysis. We find that over about three-quarters of the global land area, robust dryness changes cannot be detected. Only 10.8% of the global land area shows a robust 'dry gets drier, wet gets wetter' pattern, compared to 9.5% of global land area with the opposite pattern, that is, dry gets wetter, and wet gets drier. We conclude that aridity changes over land, where the potential for direct socio-economic consequences is highest, have not followed a simple intensification of existing patterns.
1752-0894
716-721
Greve, Peter
1d34347b-a5ad-4960-b4d3-b4f053b6a31b
Orlowsky, Boris
41d41812-b0e8-409c-8b52-032de54b2f62
Mueller, Brigitte
536eee3f-bbe4-41e5-989b-50886bcb7091
Sheffield, Justin
dd66575b-a4dc-4190-ad95-df2d6aaaaa6b
Reichstein, Markus
e0220b42-81de-4f5c-b3eb-1a6e38936b4b
Seneviratne, Sonia I.
1478d543-9dd8-4247-a416-cf51c2114b20
et al.
Greve, Peter
1d34347b-a5ad-4960-b4d3-b4f053b6a31b
Orlowsky, Boris
41d41812-b0e8-409c-8b52-032de54b2f62
Mueller, Brigitte
536eee3f-bbe4-41e5-989b-50886bcb7091
Sheffield, Justin
dd66575b-a4dc-4190-ad95-df2d6aaaaa6b
Reichstein, Markus
e0220b42-81de-4f5c-b3eb-1a6e38936b4b
Seneviratne, Sonia I.
1478d543-9dd8-4247-a416-cf51c2114b20

Greve, Peter, Orlowsky, Boris, Mueller, Brigitte and Sheffield, Justin , et al. (2014) Global assessment of trends in wetting and drying over land. Nature Geoscience, 7 (9), 716-721. (doi:10.1038/NGEO2247).

Record type: Article

Abstract

Changes in the hydrological conditions of the land surface have substantial impacts on society1,2. Yet assessments of observed continental dryness trends yield contradicting results3-7. The concept that dry regions dry out further, whereas wet regions become wetter as the climate warms has been proposed as a simplified summary of expected8-10 as well as observed10-14 changes over land, although this concept is mostly based on oceanic data8,10. Here we present an analysis of more than 300 combinations of various hydrological data sets of historical land dryness changes covering the period from 1948 to 2005. Each combination of data sets is benchmarked against an empirical relationship between evaporation, precipitation and aridity. Those combinations that perform well are used for trend analysis. We find that over about three-quarters of the global land area, robust dryness changes cannot be detected. Only 10.8% of the global land area shows a robust 'dry gets drier, wet gets wetter' pattern, compared to 9.5% of global land area with the opposite pattern, that is, dry gets wetter, and wet gets drier. We conclude that aridity changes over land, where the potential for direct socio-economic consequences is highest, have not followed a simple intensification of existing patterns.

This record has no associated files available for download.

More information

Accepted/In Press date: 12 August 2014
Published date: 1 October 2014
Additional Information: A correction has been attached to this output located at https://doi.org/10.1038/ngeo2274 In the version of this Letter originally published, in the main text, the number of different combinations given for each grid point in Fig. 3 were incorrect and should have read “28 (77)”. Additionally, the second sentence describing the parameters in the final equation should have read “Significance at the 5% level is thus assigned for n = 28 combinations of E and P data sets if and for n = 77 combinations of E and Ep data sets also if .” Furthermore, in the key for Fig. 4a, the values should have read 1.5 (−1.5). These errors have no influence on the results of the study, and have now been corrected in the online versions of the Letter.

Identifiers

Local EPrints ID: 479922
URI: http://eprints.soton.ac.uk/id/eprint/479922
ISSN: 1752-0894
PURE UUID: a94d8075-e704-471f-b4d2-77fd24b5440e
ORCID for Justin Sheffield: ORCID iD orcid.org/0000-0003-2400-0630

Catalogue record

Date deposited: 28 Jul 2023 16:52
Last modified: 06 Jun 2024 01:54

Export record

Altmetrics

Contributors

Author: Peter Greve
Author: Boris Orlowsky
Author: Brigitte Mueller
Author: Markus Reichstein
Author: Sonia I. Seneviratne
Corporate Author: et al.

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×