Mass‐Conserving Downscaling of Climate Model Precipitation Over Mountainous Terrain for Water Resource Applications

Abstract

A mass‐conserving method to downscale precipitation from global climate models (GCMs) using sub‐grid‐scale topography and modeled 700‐mb wind direction is presented. Runoff is simulated using a stand‐alone hydrological model, with this and several other methods as inputs, and compared to runoff simulated using historical observations over the western contiguous United States. Results suggest the mitigation of grid‐scale biases is more critical than downscaling for some regions with large wet biases (e.g., the Great Basin and Upper Colorado). In other regions (e.g., the Pacific Northwest) the new method produces more realistic sub‐grid‐scale variability in runoff compared to unadjusted GCM output and a simpler downscaling method. The presented method also brings the runoff centroid timing closer to that simulated with observations for all subregions examined.

Document Details

Document Type
Pub Defense Publication
Publication Date
Oct 12, 2023
Source ID
10.1029/2023gl105326

Entities

People

  • Allyson Rugg
  • Andrew J. Newman
  • Andrew W Wood
  • Ethan D. Gutmann
  • Flavio Lehner
  • Jadwiga H. Richter
  • Mari R Tye
  • Rachel McCrary

Organizations

  • Cornell University
  • Johns Hopkins University
  • National Center for Atmospheric Research
  • National Oceanic and Atmospheric Administration
  • National Science Foundation
  • Polar Bears International
  • United States Army Corps of Engineers
  • United States Department of Energy

Tags

Fields of Study

  • Environmental science

Readers

  • Atmospheric Science/Meteorology
  • Computational Modeling and Simulation
  • Wetland-Land-Environmental Management.