The Arctic is a polar region located at the northernmost part of Earth. The Arctic consists of the Arctic Ocean, adjacent seas, and parts of Canada, Danish Realm (Greenland), northern Finland, Iceland, northern Norway, Russia, northernmost Sweden and the United States (Alaska). Land within the Arctic region has seasonally varying snow and ice cover, with predominantly treeless permafrost under the tundra. Arctic seas contain seasonal sea ice in many places.
An ice shelf is a large floating platform of ice that forms where a glacier or ice sheet flows down to a coastline and onto the ocean surface. Ice shelves are only found in Antarctica, Greenland, Northern Canada, and the Russian Arctic. The boundary between the floating ice shelf and the anchor ice that feeds it is the grounding line. The thickness of ice shelves can range from about 100 m (330 ft) to 1,000 m (3,300 ft).
The Western Antarctic Ice Sheet (WAIS) is the segment of the continental ice sheet that covers West Antarctica, the portion of Antarctica on the side of the Transantarctic Mountains that lies in the Western Hemisphere. The WAIS is classified as a marine-based ice sheet, meaning that its bed lies well below sea level and its edges flow into floating ice shelves. The WAIS is bounded by the Ross Ice Shelf, the Ronne Ice Shelf, and outlet glaciers that drain into the Amundsen Sea.
The Antarctic ice sheet is one of the two polar ice caps of Earth. It covers about 98% of the Antarctic continent and is the largest single mass of ice on Earth, with an average thickness of over 2 kilometers. Separate to the Antarctic sea ice it covers an area of almost 14 million square kilometres and contains 26.5 million cubic kilometres of ice. A cubic kilometer of ice weighs approximately 0.92 metric gigatonnes, meaning that the ice sheet weighs about 24,380,000 gigatonnes. It holds approximately 61% of all fresh water on Earth, equivalent to about 58 meters of sea level rise if all the ice were above sea level. In East Antarctica, the ice sheet rests on a major land mass, while in West Antarctica the bed can extend to more than 2,500 m below sea level.
The Greenland ice sheet is a vast body of ice covering 1,710,000 square kilometres (660,000 sq mi), roughly near 80% of the surface of Greenland. It is sometimes referred to as an ice cap, or under the term inland ice, or its Danish equivalent, indlandsis. The acronym GIS is frequently used in the scientific literature.
Thwaites Glacier is an unusually broad and vast Antarctic glacier located east of Mount Murphy, on the Walgreen Coast of Marie Byrd Land. It was initially sighted by polar researchers in 1940, mapped in 1959–1966 and officially named in 1967, after the late American glaciologist Fredrik T. Thwaites. The glacier flows into Pine Island Bay, part of the Amundsen Sea, at surface speeds which exceed 2 kilometres (1.2 mi) per year near its grounding line. Its fastest-flowing grounded ice is centered between 50 and 100 kilometres east of Mount Murphy. Like many other parts of the cryosphere, it has been adversely affected by climate change, and provides one of the more notable examples of the retreat of glaciers since 1850.
Raymond S. Bradley is a climatologist and University Distinguished Professor in the Department of Geosciences at the University of Massachusetts Amherst, where he is also research director of the Climate System Research Center. Bradley's work indicates that the warming of Earth's climate system in the twentieth century is inexplicable via natural mechanisms.
The climate of the Arctic is characterized by long, cold winters and short, cool summers. There is a large amount of variability in climate across the Arctic, but all regions experience extremes of solar radiation in both summer and winter. Some parts of the Arctic are covered by ice year-round, and nearly all parts of the Arctic experience long periods with some form of ice on the surface.
Roger S. Pulwarty is a scientist from Trinidad and Tobago and contributed to the work of the Intergovernmental Panel on Climate Change (IPCC). Pulwarty is the Senior Scientist in the National Oceanic and Atmospheric Administration (NOAA) Physical Sciences Laboratory in Boulder, Colorado.
Greenland's climate is a tundra climate on and near the coasts and an ice cap climate in inland areas. It typically has short, cool summers and long, moderately cold winters.
Eric J. Rignot is the Donald Bren, Distinguished and Chancellor Professor of Earth system science at the University of California, Irvine, and a Senior Research Scientist for the Radar Science and Engineering Section at NASA's Jet Propulsion Laboratory. He studies the interaction of the polar ice sheets in Greenland and Antarctica with global climate using a combination of satellite remote sensing, airborne remote sensing, understanding of physical processes controlling glacier flow and ice melt in the ocean, field methods, and climate modeling. He was elected at the National_Academy_of_Sciences in 2018.
350.org is an international environmental organization addressing the climate crisis. Its stated goal is to end the use of fossil fuels and transition to renewable energy by building a global, grassroots movement.
Petermann Glacier is a large glacier located in North-West Greenland to the east of Nares Strait. It connects the Greenland ice sheet to the Arctic Ocean at 81°10' north latitude, near Hans Island.
Peter Sinclair from Midland, Michigan, is an environmental activist whose focus is on climate change. He is a YouTube blogger, explorer and founder of the ClimateCrocks.com website. Together with climate researchers he's traveled to hot spots of climate change, for instance to Greenland as part of the Dark Snow Project. Sinclair is perhaps best known for producing the Climate Denial Crock of the Week series on his YouTube channel. Videos have received praise from climate scientists such as Gavin Schmidt, Michael E. Mann, and the late Stephen Schneider. In 2012, he launched another YouTube series, entitled This is not Cool, for the Yale Project on Climate Change Communication.
The Dark Snow Project is a field and lab exploration to measure the impact of changing wildfire and industrial soot and snow microbes on snow and ice reflectivity.
Sea ice in the Arctic has declined in recent decades in area and volume due to climate change. It has been melting more in summer than it refreezes in winter. Global warming, caused by greenhouse gas forcing is responsible for the decline in Arctic sea ice. The decline of sea ice in the Arctic has been accelerating during the early twenty‐first century, with a decline rate of 4.7% per decade. It is also thought that summertime sea ice will cease to exist sometime during the 21st century.
Konrad "Koni" Steffen was a Swiss glaciologist, known for his research into the impact of global warming on the Arctic.
Climate change in Greenland is affecting the livelihood of the Greenlandic population. Geographically Greenland is situated between the Arctic and the Atlantic Ocean, with two thirds of the island being north of the Arctic Circle. Since the middle of the 20th century, the Arctic has been warming at about twice the global rate. Rising temperatures put increasing pressure on certain plant and tree species and contribute to Greenland's melting ice sheet. This affects and changes the livelihood of the Greenlandic population, particularly the Greenlandic Inuit, which make up to 80 percent of the total population. Besides the decline of fish stocks, the country's landscape is changing: the melting ice reveals minerals, oil and gas. This has attracted interest from local and foreign investors for potential resource extraction. As new industries are accompanied by new job opportunities and potential wealth, lifestyles are changing. Greenland is in transition, in terms of biophysical as well as cultural and social conditions.
Jacob Sebastian Haugaard Mernild is a Danish professor in climate change, glaciology and hydrology, who is the pro-vice-chancellor of the University of Southern Denmark. Mernild has been an Intergovernmental Panel on Climate Change (IPCC) author for the United Nations since 2010. Initially a contributing author on the IPCC Fifth Assessment Report, he was lead author on the IPCC Sixth Assessment Report.
Isabella Velicogna is a geoscientist known for her work using gravity measurements from space to study changes in the polar ice sheets and water storage on Earth.
