Describing the seasonal snowmelt is a vital task when assessing the impact of Climate Change on the Arctic. The general increase in local temperatures includes extreme events, marked by the presence of persistent warm and humid air masses, which have been observed not only during the summer but also, more recently, during the winter season. These unusual meteorological periods are commonly referred to as 'warm spells' and they are characterized by extended periods of exceptionally high temperatures, often accompanied by rainfall events, defined as ’rain-on-snow’ events. These events present a multitude of challenges to the delicate Arctic ecosystem and its residents, affecting the environment, ecology, and socio-economic aspects.
Although the occurrence and frequency of winter warm spells are unpredictable, their impact is widespread across both coastal and inland Arctic regions. Winter warm spells can affect the cryosphere, including terrestrial ecosystems in snow-free areas. Typically, when rain falls on existing snow cover, it forms hard crusts on the snow surface or permeates through the snowpack, resulting in pools at the snow-ground interface. This phenomenon alters the snow-albedo feedback, accelerating the hydrological cycle, and consequently increasing heat transfer even at the snow-ground interface.
Studying the effects of winter warm spells on snow throughout the entire accumulation and melting periods is essential for understanding the influence of extreme events on the Arctic environment. While identifying rain-on-snow events is well-established through satellite remote sensing and atmospheric reanalysis, assessing their impact on the environment requires further research. The objective of this initiative is to promote a dedicated workshop aimed at developing a multi-scale, multi-source strategy to comprehend the consequences of winter warm spells. The workshop seeks to leverage expertise in satellite and ground-based observations, focusing on assessing the evolution of snow and ice physics, snow chemistry, microbiology, and hydrology in supraglacial and periglacial environments.
Andrea Spolaor (Institute of Polar Science - National research council of italy (ISP-CNR), Italy)
Type of Activity:
- Talking Circle
Dates and Locations:
- June 2024
Open / Closed Activity:
Closed / by invitation only