Abstract
This study examines the net snow accumulation and ablation characteristics and trends in the Inland Temperate Rainforest (ITR) of the Upper Fraser River Basin, British Columbia (BC), Canada. It intends to establish whether elevation and/or air temperature play(s) a dominant role in hydrological year peak snow water equivalent (SWE) and whether regional patterns emerge in the interannual variability in peak accumulation. To that end, SWE and air temperature data from seven snow pillow sites in the Upper Fraser River Basin at elevations ranging from 1118 to 1847 m above sea level are analyzed to infer snowpack characteristics and trends for hydrological years 1969–2012, with 2005–2012 being the actual period of data overlap. Average peak SWE ranges from 391.3 mm at Barkerville, BC on 16 April to 924.4 mm at Hedrick Lake, BC on 27 April. Snow cover duration lasts 206–258 days, with snow onset dates from mid-October to early November and snow off dates from late May to early July. Statistically-significant (p ≤ 0.05) cross correlations exist between peak SWE at nearly all sites, indicating regional coherence in seasonal synoptic activity across the study area. However, the lack of relationships between peak SWE and elevation as well as air temperature parameters indicate that mesoscale to local processes lead to distinct snow accumulation and ablation patterns at each site. Four sites with the longest records exhibit no trend in peak SWE values between 1990 and 2012. Changes to snowpack regimes may pose a threat to the productivity and immense biodiversity supported by the ancient western red cedar and hemlock stands growing in the wet toe slopes of the ITR. Thus, it is imperative that continued monitoring of snowpack conditions remains a top priority in the Upper Fraser River Basin, allowing for a better understanding of ecosystem changes in a warming climate.
Highlights
Snow forms an important component of the hydrological cycle and climate of high latitude and mountainous regions (e.g., [1,2])
Based on the available snow pillow data, we find no relationship between hydrological year peak snow water equivalent (SWE) and site elevation or most air temperature parameters for the accumulation and ablation seasons; a clear regional pattern emerges in the interannual variability of peak snow accumulation
This study examined snow accumulation and ablation characteristics using SWE and air temperature data at seven snow pillow sites in the Inland Temperate Rainforest (ITR) of the Upper Fraser River Basin, British Columbia (BC)
Summary
Snow forms an important component of the hydrological cycle and climate of high latitude and mountainous regions (e.g., [1,2]). The Upper Fraser River Basin of British Columbia (BC), Canada, is a snow-dominated system with snowmelt resulting in an annual pulse of freshwater each spring and early summer that periodically leads to flooding. This region is dominated by abundant wintertime snowfall throughout northern BC’s mountainous terrain and vast forests. It is the site of the Inland Temperate Rainforest (ITR), an ecosystem unique to BC that is characterized by its continentality and anomalously humid climate. The continentality is depicted by the same weather systems and precipitation patterns that nourish the coastal rainforests of BC but in a cooler climate regime, creating a secondary zone of high precipitation as they cross the interior mountain ranges [3].
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have