Rain on Snow

Herders are struggling to find thousands of reindeer that have run away in search of food. "We are driving for hours and hours to locate our reindeers and to herd them back, but it has been very difficult in these wintry conditions. So, we are also using helicopters and this is very unusual - and very expensive too."

The avalanche came after two days of heavy snow followed by two days of heavy rain. The community had to wait several days before linemen could get to Chignik to repair the damage to its power system.

Peatlands make up 3 percent of the earth’s landscape, yet absorb large amounts of carbon and harbor surprising biodiversity. Although peat bogs and fens are under increasing environmental threat, efforts to protect and restore these ecosystems are gathering momentum.

As the Arctic continues to warm faster than the rest of the planet, evidence mounts that the region is experiencing unprecedented environmental change. The hydrological cycle is projected to intensify throughout the twenty-first century, with increased evaporation from expanding open water areas and more precipitation. The latest projections from the sixth phase of the Coupled Model Intercomparison Project (CMIP6) point to more rapid Arctic warming and sea-ice loss by the year 2100 than in previous projections, and consequently, larger and faster changes in the hydrological cycle. Arctic precipitation (rainfall) increases more rapidly in CMIP6 than in CMIP5 due to greater global warming and poleward moisture transport, greater Arctic amplification and sea-ice loss and increased sensitivity of precipitation to Arctic warming. The transition from a snow- to rain-dominated Arctic in the summer and autumn is projected to occur decades earlier and at a lower level of global warming, potentially under 1.5 °C, with profound climatic, ecosystem and socio-economic impacts. The Arctic warms faster than other areas of the planet, which also influences precipitation. Here, the authors show that the latest CMIP6 model ensemble shows a faster Arctic warming and sea-ice loss, causing an earlier transition from a snow- to a rain-dominated Arctic than previously thought.

Populations of southern white-tailed ptarmigan, an iconic yet well-camouflaged and easily overlooked bird of Colorado’s alpine regions, appear to be holding steady. But long-term concerns about its future remain in a warming world with growing numbers of people recreating in the state’s fragile alpine ecosystems.

Bulldozer crews have cleared trails and fields for the bison in hopes of reducing the danger of collisions and damaged fields. There's a layer of ice up to two inches thick within the snowpack that has further complicated foraging.

An inch of rain in late December left a sheet of ice around Fairbanks that is altering life for a bevy of species.

"Even ordinary rainfall can be regarded as an extreme event in polar regions," Dou said. This is because rain-on-snow events, which occur when rain falls onto an existing snowpack and freezes into an ice crust, impact wildlife, infrastructure and local communities.

Unusual weather patterns in Sweden’s arctic region seem to be jeopardising the migrating animals’ traditional grazing grounds, as rainfall during the winter has led to thick layers of snowy ice that block access to food.

This summer, for the first time on record, rain fell on Greenland’s frozen summit. The Northern Hemisphere experienced warmer-than-usual summer temperatures this year, and even the coldest environments are being impacted.