Ice cover changes in 70 years period on the North Caspian.

The glacier extends through the Illulisat Icefjord, surrounded by mountains. Icebergs calve off from the main glacier, pile up and block the fjord before being released into Qeqertarsuup Tunua (Disko) Bay and Davis Strait. The whiter areas in the fjord are piledup icebergs and the “real” glacier ends where the greyish striped section ends – showing that this image is from 2001. The graph shows glacier-velocity profiles for 1985 to 2006. During th...

Passive microwave sensors on satellites have monitored the extent of the sea ice cover since 19782. This technique is widely used to investigate fluctuations in ice extent over the seasons, variability between years, and longterm trends. The seasonal variation of ice extent is much greater in the Antarctic where there is about six times as much ice in winter as in summer. Currently, in the Arctic, ice approximately doubles from summer to winter. ...

The lines represent IPCC Special Report on Emissions Scenarios (SRES) based on different world views. The differences in impacts between the SRES scenarios for the same amount of sea-level rise and protection response reflect differences in exposure (population) and ability to adapt (wealth). The solid lines represent a level of 'constant' (no additional) protection response. The dashed and dotted lines represent the addition of protection respon...

Feedback refers to the modification of a process by changes resulting from the process itself. Positive feedbacks accelerate the process, while negative feedbacks slow it down. Part of the uncertainty around future climates relates to important feedbacks between different parts of the climate system: air temperatures, ice and snow albedo (reflection of the sun’s rays), and clouds. An important positive feedback is the ice and snow albedo feedback...

Arctic marine systems currently provide a substantial carbon sink but the continuation of this service depends critically on arctic climate change impacts on ice, freshwater inputs, and ocean acidification.

Sea ice has decreased sharply in all seasons, with summer sea ice declining most dramatically — beyond the projections of IPCC 2007.

Temperature monitoring in Canada indicates a warming of shallow permafrost over the last two to three decades. Since the mid-1980s, shallow permafrost (upper 20-30 m) has generally warmed in the Mackenzie Valley. The greatest increases in temperature were 0.3 to 1°C per decade in the cold and thick permafrost of the central and northern valley. In the southern Mackenzie Valley, where permafrost is thin and close to 0°C, no significant trend in pe...

The global conveyor belt thermohaline circulation is driven primarily by the formation and sinking of deep water (from around 1500m to the Antarctic bottom water overlying the bottom of the ocean) in the Norwegian Sea. When the strength of the haline forcing increases due to excess precipitation, runoff, or ice melt the conveyor belt will weaken or even shut down. The variability in the strength of the conveyor belt will lead to climate change in...

The most recent geological history, in the last hundred thousand years, has been characterised by cycles of glaciations, or ice ages. The historic temperatures, through these times, have been low, and continental ice sheets have covered large parts of the world. Through ancient air, trapped in tiny bubbles in the Antarctic ice, we have been able to see what the temperature cycle was at that time, and also the concentration of carbon dioxide (CO2)...

Major glacier hazard locations

The red line indicates the median minimum extent of the ice cover for the period 1979–2000. This figure compares the Arctic sea ice extent in September for the years 1982 (the record maximum since 1979), 2005 and 2007 (the record minimum). The ice extent was 7.5 million km2 in 1982 and only 5.6 million km2 in 2005 and down to 4.3 million km2 in 2007. As has been observed in other recent years, the retreat of the ice cover was particularly pronoun...

Warming is widespread, generally greater over land than over oceans, and the largest gains in temperatures for the planet are over the North American Arctic, north central Siberia, and on the Antarctic Peninsula. These recent increases in temperature are confirmed by changes in other features: loss of sea ice, shift of tundra to shrub vegetation, and migration of marine and terrestrial ecosystems to higher latitudes.

Ringed seals are the 'classic' Arctic seal in many regards, being found as far north as the Pole because of their ability to keep breathing holes open in ice that can reach 2 metres in depth. This species is certainly one of the most vulnerable of the high-Arctic seals to the declines in the extent or quality of sea ice because so many aspects of their life-history and distribution are tied to ice. Ringed seals also require sufficient snow cover...

Mass-balance estimates for Greenland show thickening at high elevations since the early 1990s at rates that increased to about 4 cm per year after 2000, consistent with expectations of increasing snowfall in a warming climate. However, this mass gain is far exceeded by losses associated with large increases in thinning of the ice sheet near the coast. Total loss from the ice sheet more than doubled, from a few tens of billions of tonnes per year ...

Arctic Ocean circulate in a large clockwise rotational pattern moving from east to west around the polar ice cap. This rotating pattern, known as a gyre, occurs as a result of the clockwise winds that typically occur in this region. The Barents region is affected by this and the ice edge extent in the Arctic.

At the February 2001 meeting of the American Association for the Advancement of Science (AAAS), researchers reported dramatic changes in the volume of ice capping the Kibo summit of Kilimanjaro.This graphic shows the estimated extent of the glacier on Mount Kilimanjaro in 1912, and the extent of the glaciers there in 2002. The graphic also shows the decline in the total area of the ice from 1900 to 2000, with projected data to the year 2020.

Thickness, in relation to elevation, for two different ice fields located in very Southern South America (Patagonian ice fields), with 1975-2000 averages and 1995-2000 average, which show dramatic decrease.

Several mountain glaciers now disappear at a frightening rate as in the Santa Rosa glacier of Peru. A warmer climate often leads to increased precipitation. Much of the increased precipitation comes as rain instead of snow, mostly in the winter and to a lesser extent during the autumn and the spring. The winter rains fall over existing snow, causing increased melting. As the ice and snow cover is reduced, the albedo of the area is reduced as we...

Shows the retreat of the glacier on the volcano Nevado Santa Isabel and the correlation of global warming. With spectacular mountain peak glaciers melting away, the area becomes less attractive to tourists. In addition, the local forestry and agricultural fertility suffer.