U.S. Department of Agriculture: Forest Service -- National Agroforestry Center
ORCID IDs
https://orcid.org/0000-0002-0024-7965
https://orcid.org/0000-0002-2186-2625
https://orcid.org/0000-0002-2968-3023
https://orcid.org/0000-0002-2923-1203
https://orcid.org/0000-0003-4320-2342
https://orcid.org/0000-0001-9201-1062
https://orcid.org/0000-0002-7240-9265
https://orcid.org/0000-0002-3012-5192
https://orcid.org/0000-0001-6577-3619
https://orcid.org/0000-0003-0477-9755
https://orcid.org/0000-0003-4389-3139
https://orcid.org/0000-0001-8780-8501
https://orcid.org/0000-0003-1463-308X
https://orcid.org/0000-0001-6883-7630
https://orcid.org/0000-0001-7120-1713
https://orcid.org/0000-0003-3107-4689
https://orcid.org/0000-0001-7625-4507
https://orcid.org/0000-0002-0702-2646
https://orcid.org/0000-0001-9195-6419
https://orcid.org/0000-0002-4316-2013
https://orcid.org/0000-0003-3881-5849
https://orcid.org/0000-0001-7352-2764
https://orcid.org/0000-0002-8199-3264
https://orcid.org/0000-0001-9154-9485
https://orcid.org/0000-0001-5445-2473
https://orcid.org/0000-0001-9381-7279
https://orcid.org/0000-0002-4062-0322
https://orcid.org/0000-0003-0529-3925
https://orcid.org/0000-0002-0685-1901
https://orcid.org/0000-0001-9994-1545
Document Type
Article
Date of this Version
2-27-2019
Citation
2019. American Geophysical Union.
Abstract
Earth System Models (ESMs) are essential tools for understanding and predicting global change, but they cannot explicitly resolve hillslope‐scale terrain structures that fundamentally organize water, energy, and biogeochemical stores and fluxes at subgrid scales. Here we bring together hydrologists, Critical Zone scientists, and ESM developers, to explore how hillslope structures may modulate ESM grid‐level water, energy, and biogeochemical fluxes. In contrast to the one‐dimensional (1‐D), 2‐ to 3‐mdeep, and free‐draining soil hydrology in most ESM land models, we hypothesize that 3‐D, lateral ridge‐to‐valley flow through shallow and deep paths and insolation contrasts between sunny and shady slopes are the top two globally quantifiable organizers of water and energy (and vegetation) within an ESM grid cell. We hypothesize that these two processes are likely to impact ESM predictions where (and when) water and/or energy are limiting. We further hypothesize that, if implemented in ESM land models, these processes will increase simulated continental water storage and residence time, buffering terrestrial ecosystems against seasonal and interannual droughts. We explore efficient ways to capture these mechanisms in ESMs and identify critical knowledge gaps preventing us from scaling up hillslope to global processes. One such gap is our extremely limited knowledge of the subsurface, where water is stored (supporting vegetation) and released to stream baseflow (supporting aquatic ecosystems). We conclude with a set of organizing hypotheses and a call for global syntheses activities and model experiments to assess the impact of hillslope hydrology on global change predictions.
Included in
Forest Biology Commons, Forest Management Commons, Other Forestry and Forest Sciences Commons, Plant Sciences Commons
Comments
Fan, Y., Clark, M., Lawrence, D. M., Swenson, S., Band, L. E., Brantley, S. L., et al. (2019). Hillslope hydrology in global change research and Earth system modeling. Water Resources Research, 55, 1737–1772. https://doi. org/10.1029/2018WR023903