Widespread warming trends in storm temperatures and snowpack fate across the Western United States

Hu, J. Michelle; Nolin, A. W.

doi:10.1088/1748-9326/ab763f

Cited by 12 publications

(8 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We saw an increase in winter temperature (December-February) of 0.82 • C/decade as an average between the 22 stations. Similar warming was reported by Hu and Nolin [58], who indicated a warming trend of 0.4-1.2 • C/decade for the Interior West. Other studies also estimated warming rates of about 0.5 • C/decade [56,59,60], which are similar to the trends in yearly average air temperatures reported in this study (0.33 to 1.03 • C/decade).…”

Section: Discussionsupporting

confidence: 88%

Multiple Indicators of Extreme Changes in Snow-Dominated Streamflow Regimes, Yakima River Basin Region, USA

Wagner

Bennett

Liston

et al. 2021

Water

View full text Add to dashboard Cite

Snow plays a major role in the hydrological cycle. Variations in snow duration and timing can have a negative impact on water resources. Excluding predicted changes in snowmelt rates and amounts could result in deleterious infrastructure, military mission, and asset impacts at military bases across the US. A change in snowpack can also lead to water shortages, which in turn can affect the availability of irrigation water. We performed trend analyses of air temperature, snow water equivalent (SWE) at 22 SNOTEL stations, and streamflow extremes for selected rivers in the snow-dependent and heavily irrigated Yakima River Basin (YRB) located in the Pacific Northwest US. There was a clear trend of increasing air temperature in this study area over a 30 year period (water years 1991–2020). All stations indicated an increase in average air temperatures for December (0.97 °C/decade) and January (1.12 °C/decade). There was also an upward trend at most stations in February (0.28 °C/decade). In December–February, the average air temperatures were 0.82 °C/decade. From these trends, we estimate that, by 2060, the average air temperatures for December–February at most (82%) stations will be above freezing. Furthermore, analysis of SWE from selected SNOTEL stations indicated a decreasing trend in historical SWE, and a shift to an earlier peak SWE was also assumed to be occurring due of the shorter snow duration. Decreasing trends in snow duration, rain-on-snow, and snowmelt runoff also resulted from snow modeling simulations of the YRB and the nearby area. We also observed a shift in the timing of snowmelt-driven peak streamflow, as well as a statistically significant increase in winter maximum streamflow and decrease in summer maximum and minimum streamflow trends by 2099. From the streamflow trends and complementary GEV analysis, we show that the YRB basin is a system in transition with earlier peak flows, lower snow-driven maximum streamflow, and higher rainfall-driven summer streamflow. This study highlights the importance of looking at changes in snow across multiple indicators to develop future infrastructure and planning tools to better adapt and mitigate changes in extreme events.

show abstract

Section: Discussionsupporting

confidence: 88%

Multiple Indicators of Extreme Changes in Snow-Dominated Streamflow Regimes, Yakima River Basin Region, USA

Wagner

Bennett

Liston

et al. 2021

Water

View full text Add to dashboard Cite

show abstract

“…We constrained most of our attention to these two 6‐month periods due to both applied and statistical purposes. First, the covariance structure of temperature and precipitation during the cool season is important in shaping snowpack development (Hu & Nolin, 2020), while the daily covariance structure in the warm season is important for vegetation moisture stress through vapor pressure deficits (Hsiao et al., 2019). Second, our focus on the top 10% of wet days limits robust statistical analysis of trends with traditional 3‐month climatological seasons at sites with infrequent wet days.…”

Section: Methodsmentioning

confidence: 99%

Precipitation Dependence of Temperature Trends Across the Contiguous US

Abatzoglou

Marshall

Lute

et al. 2022

Geophysical Research Letters

View full text Add to dashboard Cite

Warming trends and their patterns are well established across the globe and largely attributable to anthropogenic forcing (Bindoff et al., 2013). Trends in regional temperature on seasonal and diurnal scales can exhibit notable differences from continental and global trends due to a consortium of factors including changes in circulation patterns (Abatzoglou & Redmond, 2007), land-use change (Christidis et al., 2013), changes in aerosols (Lelieveld et al., 2019), and concurrent trends in soil moisture (Vogel et al., 2017). Complementary to standard summaries of temperature trends (e.g., annual mean temperature), insight on climate change and associated impacts may be gained by decomposing temperature trends based on precipitation occurrence and amount. The covariance structure of daily temperature and precipitation and changes thereof have several notable impacts on hydrologic and ecological systems. For example, near the climatological freezing-level, the relationship between temperature and precipitation occurrence and amount can impact flood hazards (Musselman et al., 2018), snowpack storage (Klos et al., 2014), and water supply (Berghuijs et al., 2014). Likewise, differences in temperatures during the warm season between dry days and wet days impact vegetative moisture stress through altered evaporative demand with impacts to both agriculture and ecosystems (Holden et al., 2018).Air temperature is sensitive to local radiation budgets and the advection of air masses associated with precipitation occurrence and intensity (Berg et al., 2009;Isaac & Stuart, 1992). For example, subtropical transport of warm moist air in atmospheric rivers during winter leads to anomalously warm daily minimum temperatures across the mountains of the western United States (US; Hu & Nolin, 2019), while reduced downward shortwave radiation during wet days in the warm season suppresses daily maximum temperature. Studies have examined

show abstract

“…In contrast, warmer than average winter temperatures that lead to a shift from snowfall to rainfall is termed a “warm snow drought” (Harpold et al, 2017) and may be caused by overall increases in winter storm temperatures. Warm snow droughts are most pronounced at low elevations and in maritime snow regions such as the Oregon and Washington Cascades and the California Sierra Nevada, where storm temperatures are close to the melting point (Hu & Nolin, 2020).…”

Section: Previously Developed Snow Metrics and Their Limitationsmentioning

confidence: 99%

New snow metrics for a warming world

Nolin

Sproles

Rupp

et al. 2021

Hydrological Processes

View full text Add to dashboard Cite

Snow is Earth's most climatically sensitive land cover type. Traditional snow metrics may not be able to adequately capture the changing nature of snow cover. For example, April 1 snow water equivalent (SWE) has been an effective index for streamflow forecasting, but it cannot express the effects of midwinter melt events, now expected in warming snow climates, nor can we assume that station‐based measurements will be representative of snow conditions in future decades. Remote sensing and climate model data provide capacity for a suite of multi‐use snow metrics from local to global scales. Such indicators need to be simple enough to “tell the story” of snowpack changes over space and time, but not overly simplistic or overly complicated in their interpretation. We describe a suite of spatially explicit, multi‐temporal snow metrics based on global satellite data from NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) and downscaled climate model output for the U.S. We describe and provide examples for Snow Cover Frequency (SCF), Snow Disappearance Date (SDD), At‐Risk Snow (ARS), and Frequency of a Warm Winter (FWW). Using these retrospective and prospective snow metrics, we assess the current and future snow‐related conditions in three hydroclimatically different U.S. watersheds: the Truckee, Colorado Headwaters, and Upper Connecticut. In the two western U.S. watersheds, SCF and SDD show greater sensitivity to annual differences in snow cover compared with data from the ground‐based Snow Telemetry (SNOTEL) network. The eastern U.S. watershed does not have a ground‐based network of data, so these MODIS‐derived metrics provide uniquely valuable snow information. The ARS and FWW metrics show that the Truckee Watershed is highly vulnerable to conversion from snowfall to rainfall (ARS) and midwinter melt events (FWW) throughout the seasonal snow zone. In comparison, the Colorado Headwaters and Upper Connecticut Watersheds are colder and much less vulnerable through mid‐ and late‐century.

show abstract

Widespread warming trends in storm temperatures and snowpack fate across the Western United States

Cited by 12 publications

References 47 publications

Multiple Indicators of Extreme Changes in Snow-Dominated Streamflow Regimes, Yakima River Basin Region, USA

Multiple Indicators of Extreme Changes in Snow-Dominated Streamflow Regimes, Yakima River Basin Region, USA

Precipitation Dependence of Temperature Trends Across the Contiguous US

New snow metrics for a warming world

Contact Info

Product

Resources

About