When will the summer Arctic be nearly sea ice free?

  title={When will the summer Arctic be nearly sea ice free?},
  author={James E. Overland and Muyin Wang},
  journal={Geophysical Research Letters},
The observed rapid loss of thick multiyear sea ice over the last 7 years and the September 2012 Arctic sea ice extent reduction of 49% relative to the 1979–2000 climatology are inconsistent with projections of a nearly sea ice‐free summer Arctic from model estimates of 2070 and beyond made just a few years ago. Three recent approaches to predictions in the scientific literature are as follows: (1) extrapolation of sea ice volume data, (2) assuming several more rapid loss events such as 2007 and… 

Nonuniform Contribution of Internal Variability to Recent Arctic Sea Ice Loss

Over the last half century, the Arctic sea ice cover has declined dramatically. Current estimates suggest that, for the Arctic as a whole, nearly one-half of the observed loss of summer sea ice

Arctic sea-ice loss is projected to lead to more frequent strong El Niño events

Arctic sea ice has decreased substantially and is projected to reach a seasonally ice-free state in the coming decades. Little is known about whether dwindling Arctic sea ice is capable of

Sensitivity Analysis of Arctic Sea Ice Extent Trends and Statistical Projections Using Satellite Data

The results from a sensitivity analysis of six commonly used curve-fitting models show that the projected timings of the first Arctic ice-free summer year tend to be earlier for exponential, Gompertz, quadratic, and linear with lag fittings, and later for linear and log fittings.

Arctic sea ice in transformation: A review of recent observed changes and impacts on biology and human activity

Sea ice in the Arctic is one of the most rapidly changing components of the global climate system. Over the past few decades, summer areal extent has declined over 30%, and all months show

On the Potential for Abrupt Arctic Winter Sea Ice Loss

AbstractThe authors examine the transition from a seasonally ice-covered Arctic to an Arctic Ocean that is sea ice free all year round under increasing atmospheric CO2 levels. It is shown that in

The Arctic-Subarctic sea ice system is entering a seasonal regime: Implications for future Arctic amplification

It is shown that the Arctic-Subarctic, i.e. the northern hemisphere, sea ice now exhibits similar levels of seasonality to the Antarctic, which is in a seasonal regime without significant change since satellite observations began in 1979.

New observations of Arctic sea ice from satellite radar altimetry

Satellite observations of Arctic sea ice have observed a decline in extent for all months since 1979. The decline is coincident with abrupt global and Arctic warming over the last 30 years. Over this

Toward an ice‐free Barents Sea

Arctic winter sea ice loss is most pronounced in the Barents Sea. Here we combine observations since 1850 with climate model simulations to examine the recent record low winter Barents Sea ice

How predictable is the timing of a summer ice‐free Arctic?

Climate model simulations give a large range of over 100 years for predictions of when the Arctic could first become ice free in the summer, and many studies have attempted to narrow this uncertainty



A sea ice free summer Arctic within 30 years?

September 2008 followed 2007 as the second sequential year with an extreme summer Arctic sea ice extent minimum. Although such a sea ice loss was not indicated until much later in the century in the

A sea ice free summer Arctic within 30 years: An update from CMIP5 models

Three years ago we proposed that the summer Arctic would be nearly sea ice free by the 2030s; “nearly” is interpreted as sea ice extent less than 1.0 million km2. We consider this estimate to be

Constraining projections of summer Arctic sea ice

We examine the recent (1979–2010) and future (2011–2100) characteristics of the summer Arctic sea-ice cover as simulated by 37 Earth system and general circulation models from the Coupled Model

Trends in Arctic sea ice extent from CMIP5, CMIP3 and observations

The rapid retreat and thinning of the Arctic sea ice cover over the past several decades is one of the most striking manifestations of global climate change. Previous research revealed that the

CryoSat‐2 estimates of Arctic sea ice thickness and volume

Satellite records show a decline in ice extent over more than three decades, with a record minimum in September 2012. Results from the Pan‐Arctic Ice‐Ocean Modelling and Assimilation system (PIOMAS)

Recovery mechanisms of Arctic summer sea ice

We examine the recovery of Arctic sea ice from prescribed ice‐free summer conditions in simulations of 21st century climate in an atmosphere–ocean general circulation model. We find that ice extent

What drove the dramatic retreat of arctic sea ice during summer 2007?

A model study has been conducted of the unprecedented retreat of arctic sea ice in the summer of 2007. It is found that preconditioning, anomalous winds, and ice‐albedo feedback are mainly

The reversibility of sea ice loss in a state‐of‐the‐art climate model

Rapid Arctic sea ice retreat has fueled speculation about the possibility of threshold (or ‘tipping point’) behavior and irreversible loss of the sea ice cover. We test sea ice reversibility within a

Inter‐annual to multi‐decadal Arctic sea ice extent trends in a warming world

A climate model (CCSM4) is used to investigate the influence of anthropogenic forcing on late 20th century and early 21st century Arctic sea ice extent trends. On all timescales examined (2–50+

The Future of Arctic Sea Ice

Arctic sea ice is a key indicator of the state of global climate because of both its sensitivity to warming and its role in amplifying climate change. Accelerated melting of the perennial sea ice