Reporting from the front line of climate change

Snow, Water, Ice and Permafrost in the Arctic: monitoring report

A recent report by SWIPA looked at the changes facing the Arctic region, and described many impacts which were based on observations and research.

Key findings of the 2017 SWIPA report

• The period 2011 – 2015 was the warmest ever recorded in the Arctic. Higher surface air temperatures are driving changes in the cryosphere.
• Changes include loss of sea ice and snow, melting of glaciers and ice sheets, freshening and warming of the Arctic Ocean, thawing of permafrost and ecological shifts.
• The Arctic has been warming more than twice as rapidly as the world as a whole for the past 50 years. Models project that by 2100 temperatures will increase by 6 – 12°C in the winter months.
• The extent and duration of snow cover and sea ice have decreased across the Arctic region. The Arctic Ocean is predicted to become ice free in summer by the late 2030s, earlier than previously thought.
• Most sea ice in the Arctic is now seasonal ice that grows in the winter and melts in the spring and summer. Prior to 2007, more of the ice lasted over a year (perennial ice)
• The annual duration of snow cover is decreasing by 2 – 4 days per decade and is projected to decrease by up to a further 10-20% by 2050.
• Near-surface permafrost in the High Arctic and other very cold areas has warmed by 0.5° since 2007-9, and the depth of the active layer has increased. The area of near-surface permafrost is projected to decline by 35% by 2050.
• Release of carbon dioxide and methane from the melting permafrost could further enhance climate change, as Arctic soils hold 50% of the world’s soils carbon.
• Global sea level is projected to rise by between 52 and 74 cm by 2100 and Arctic ice loss will make a substantial contribution to this. It currently accounts for 35% of global sea level rise.
• Meltwater from Arctic glaciers, ice caps and ice sheets contributes to over a third of global sea level rise. Meltwater from the Greenland ice sheet accounts for 70% of this – enough since 2000 to raise global sea level by 1 cm.
• Changes in the cryosphere cause fundamental changes to the characteristics of Arctic ecosystems, altering species’ ranges, diets, habitats, migrations and predator-prey relationships.
• The observed and expected future changes to the Arctic cryosphere will impact on human populations locally and globally. A recent economic analysis put the global cost of Arctic change at between USD $7 and 90 trillion between 2010 and 2100.
• Locally, transport options and access to resources are radically changed by differences in the distribution and seasonal occurrence of snow, water, ice and permafrost in the Arctic. For example, roads may be affected, resulting in restricted access to remote communities.
• Arctic infrastructure faces increased risks of damage due to changes in the cryosphere, particularly the loss of permafrost and land-fast sea ice.
• Other local hazards include coastal erosion, the mobility of sea ice, and a higher risk of wildfire, avalanches and flooding.
• There are also new opportunities. The Arctic Ocean’s open water season has already increased by between 1 and 3 months since the late 1970s, opening more shipping routes and access to oil and mineral resources, and creating opportunities for tourism.
• Globally, changes to ocean circulation patterns driven by the warming of the Arctic and associated ice melt could have a significant influence on the climate of regions as far south as the tropics, cooling the Northern Hemisphere and altering the onset and rainfall of the South East Asian monsoon.
• There remains a great deal of uncertainty about future change in the Arctic cryosphere. However, even if the target of 2°C warming by 2100 set by the 2015 Paris Agreement is reached, there will still be significant impacts. Even under this scenario, warming in the Arctic will be between 4 and 6°C due to strong feedback mechanisms.
• The 2017 SWIPA report makes three main recommendations: reducing greenhouse gas emissions above and beyond the Paris Agreement targets, adapting to change, and conducting further scientific research to improve understanding of the mechanisms of climate change.