Preprints
https://doi.org/10.5194/egusphere-2024-2284
https://doi.org/10.5194/egusphere-2024-2284
16 Aug 2024
 | 16 Aug 2024
Status: this preprint is open for discussion.

Dynamic precipitation phase partitioning improves modeled simulations of snow across the Northwest US

Bhupinderjeet Singh, Mingliang Liu, John Abatzoglou, Jennifer Adam, and Kirti Rajagopalan

Abstract. While the importance of dynamic precipitation phase partitioning to get accurate estimates of rain versus snow amounts has been established, hydrology models rely on simplistic static temperature-based partitioning. We evaluate model skill changes for a suite of snow metrics between static and dynamic partitioning. We used the VIC-CropSyst coupled crop hydrology model across the Pacific Northwest US as a case study. We found that transition to the dynamic method resulted in a better match between modeled and observed (a) peak snow water equivalent (SWE) magnitude and timing (~50 % mean error reduction), (b) daily SWE in winter months (reduction of relative bias from -30 % to -4 %), and (c) snow-start dates (mean reduction in bias from 7 days to 0 days) for a majority of the observational snow telemetry stations considered (depending on the metric, 75 % to 88 % of stations showed improvements). However, there was a degradation in model-observation agreement for snow-off dates, likely because errors in modeled snowmelt dynamics—which cannot be resolved by changing the precipitation partitioning—become important at the end of the cold season. Additionally, the transition from static to dynamic partitioning resulted in an 8 % mean increase in the snowmelt contribution to runoff. These results emphasize that the hydrological modeling community should transition to incorporating dynamic precipitation partitioning so we can better understand model behavior, improve model accuracies, and better support management decision support for water resources.

Publisher's note: Copernicus Publications remains neutral with regard to jurisdictional claims made in the text, published maps, institutional affiliations, or any other geographical representation in this preprint. The responsibility to include appropriate place names lies with the authors.
Bhupinderjeet Singh, Mingliang Liu, John Abatzoglou, Jennifer Adam, and Kirti Rajagopalan

Status: open (until 18 Oct 2024)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
Bhupinderjeet Singh, Mingliang Liu, John Abatzoglou, Jennifer Adam, and Kirti Rajagopalan
Bhupinderjeet Singh, Mingliang Liu, John Abatzoglou, Jennifer Adam, and Kirti Rajagopalan

Viewed

Total article views: 200 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
135 55 10 200 19 4 5
  • HTML: 135
  • PDF: 55
  • XML: 10
  • Total: 200
  • Supplement: 19
  • BibTeX: 4
  • EndNote: 5
Views and downloads (calculated since 16 Aug 2024)
Cumulative views and downloads (calculated since 16 Aug 2024)

Viewed (geographical distribution)

Total article views: 237 (including HTML, PDF, and XML) Thereof 237 with geography defined and 0 with unknown origin.
Land # Ansichten %
  • 1
1
 
 
 
 
Latest update: 13 Sep 2024
Download
Short summary
Hydrology models rely on simplistic static approaches to precipitation phase partitioning. We evaluate model skill changes for a suite of snow metrics by transitioning to a more accurate dynamic partitioning. We found that the transition resulted in a better match between modeled and observed metrics, with a 50 % reduction in model bias, emphasizing the need for the hydrological modeling community to adopt dynamic partitioning.