David Crowder and Gengping Zhu explain how to predict the spread of the Asian giant hornet.
New Research In
Physical Sciences
Featured Portals
Articles by Topic
Biological Sciences
Featured Portals
Articles by Topic
Edited by Benjamin D. Santer, Lawrence Livermore National Laboratory, Livermore, CA, and approved June 23, 2020 (received for review September 17, 2019)
Significance
Given the importance of snow to global food, water, and energy security, characterizing snow deficits (snow droughts) in a changing climate has emerged as a critical knowledge gap. We identify snow drought hot spots and determine how drought duration and intensity vary globally. We show that eastern Russia, Europe, and the western United States experienced longer, more intense snow droughts in the second half of the period 1980 to 2018. During this period, droughts became less intense over the Hindu Kush, Himalayas, extratropical Andes, and Patagonia regions. Natural and human-driven factors (e.g., atmospheric circulation patterns, polar vortex movement, and Arctic warming) likely contribute to snow droughts. We urge the community to further investigate the complex physical drivers of snow drought.
Abstract
Snow plays a fundamental role in global water resources, climate, and biogeochemical processes; however, no global snow drought assessments currently exist. Changes in the duration and intensity of droughts can significantly impact ecosystems, food and water security, agriculture, hydropower, and the socioeconomics of a region. We characterize the duration and intensity of snow droughts (snow water equivalent deficits) worldwide and differences in their distributions over 1980 to 2018. We find that snow droughts became more prevalent, intensified, and lengthened across the western United States (WUS). Eastern Russia, Europe, and the WUS emerged as hot spots for snow droughts, experiencing ∼2, 16, and 28% longer snow drought durations, respectively, in the latter half of 1980 to 2018. In this second half of the record, these regions exhibited a higher probability (relative to the first half of the record) of having a snow drought exceed the average intensity from the first period by 3, 4, and 15%. The Hindu Kush and Central Asia, extratropical Andes, greater Himalayas, and Patagonia, however, experienced decreases (percent changes) in the average snow drought duration (−4, −7, −8, and −16%, respectively). Although we do not attempt to separate natural and human influences with a detailed attribution analysis, we discuss some relevant physical processes (e.g., Arctic amplification and polar vortex movement) that likely contribute to observed changes in snow drought characteristics. We also demonstrate how our framework can facilitate drought monitoring and assessment by examining two snow deficits that posed large socioeconomic challenges in the WUS (2014/2015) and Afghanistan (2017/2018).
Footnotes
- ↵1To whom correspondence may be addressed. Email: lhuning{at}uci.edu.
Author contributions: L.S.H. and A.A. designed research; L.S.H. performed research; L.S.H. analyzed data; and L.S.H. and A.A. wrote the paper.
The authors declare no competing interest.
This article is a PNAS Direct Submission.
Data deposition: Data supporting the conculsions in this study can be obtained from https://doi.org/10.6084/m9.figshare.c.5055179. Modern-Era Retrospective Analysis for Research and Applications, version 2, data are available from https://gmao.gsfc.nasa.gov/reanalysis/MERRA-2/data_access/. Moderate Resolution Imaging Spectroradiometer (MODIS)/Terra monthly snow cover data are available from https://doi.org/10.5067/MODIS/MOD10CM.006. The Snow Data Assimilation System and Famine Early Warning System Network snow water equivalent information used in SI Appendix over the contiguous United States and Afghanistan can be downloaded from https://doi.org/10.7265/N5TB14TC and https://earlywarning.usgs.gov/fews/product/188, respectively.
This article contains supporting information online at https://www.pnas.org/lookup/suppl/doi:10.1073/pnas.1915921117/-/DCSupplemental.
Data Availability.
Data supporting the conclusions of this study can be obtained from https://doi.org/10.6084/m9.figshare.c.5055179. MERRA-2 data are available from https://gmao.gsfc.nasa.gov/reanalysis/MERRA-2/data_access/. MODIS/Terra monthly snow cover data are available from https://doi.org/10.5067/MODIS/MOD10CM.006. The SNODAS and FEWS NET SWE information used in SI Appendix over CONUS and Afghanistan can be downloaded from https://doi.org/10.7265/N5TB14TC and https://earlywarning.usgs.gov/fews/product/188, respectively.
Published under the PNAS license.
References
Log in using your username and password
Log in through your institution
You may be able to gain access using your login credentials for your institution. Contact your library if you do not have a username and password.
If your organization uses OpenAthens, you can log in using your OpenAthens username and password. To check if your institution is supported, please see this list. Contact your library for more details.
Purchase access
You may purchase access to this article. This will require you to create an account if you don't already have one.
Global snow drought hot spots and characteristics
Sign up for Article Alerts
Article Classifications
- Physical Sciences
- Earth, Atmospheric, and Planetary Sciences
Jump to section
You May Also be Interested in
If we don’t clarify terms, we risk hampering the field, confusing the public, and possibly losing a technology that may help solve some of the world’s most intractable problems.
Image credit: Stephanie Gamez (University of California San Diego, La Jolla, CA).
A small fossil reptile related to dinosaurs and pterosaurs suggests a miniaturized origin for some of the largest animals to live on Earth.
Image credit: Alex Boersma (artist).
A 1.4-million-year-old handaxe made from hippopotamus bone expands the known technological repertoire of early human ancestors.
Image credit: Berhane Asfaw.
Ancestors of domestic cats may have existed in a commensal but not yet domesticated relationship with Neolithic farmers.
Image credit: Michał Wojenka and Magdalena Krajcarz.