North pole soon to be ice free in summer

April 20, 2020

The Arctic Ocean in summer will very likely be ice free before 2050, at least temporally. The efficacy of climate-protection measures will determine how often and for how long. These are the results of a new research study involving 21 research institutes from around the world, coordinated by Dirk Notz from the University of Hamburg, Germany.

The research team has analyzed recent results from 40 different climate models. Using these models, the researchers considered the future evolution of Arctic sea-ice cover in a scenario with high future CO2 emissions and little climate protection. As expected, Arctic sea ice disappeared quickly in summer in these simulations. However, the new study finds that Arctic summer sea ice also disappears occasionally if CO2 emissions are rapidly reduced.

"If we reduce global emissions rapidly and substantially, and thus keep global warming below 2 °C relative to preindustrial levels, Arctic sea ice will nevertheless likely disappear occasionally in summer even before 2050. This really surprised us" said Dirk Notz, who leads the sea-ice research group at University of Hamburg, Germany.

Currently, the North Pole is covered by sea ice year round. Each summer, the area of the sea ice cover decreases, in winter it grows again. In response to ongoing global warming, the overall area of the Arctic Ocean that is covered by sea ice has rapidly been reduced over the past few decades. This substantially affects the Arctic ecosystem and climate: The sea-ice cover is a hunting ground and habitat for polar bears and seals, and keeps the Arctic cool by reflecting sunlight.

How often the Arctic will lose its sea-ice cover in the future critically depends on future CO2 emissions, the study shows. If emissions are reduced rapidly, ice-free years only occur occasionally. With higher emissions, the Arctic Ocean will become ice free in most years. Hence, humans still have an impact on how often the Arctic loses its year-round sea-ice cover.

Technical details: The simulations used in this study are based on so-called SSP Scenarios (shared socio-economic pathways), which will also be used for the next IPCC report. Scenarios SSP1-1.9 and SSP1-2.6 are used to simulate a rapid reduction of future CO2 emissions, while scenario SSP5-8.5 is used to simulate largely unchanged future CO2 emissions. The study is based on simulations from the most recent generation of climate models, collected within the Coupled Model Intercomparison Project Phase 6 (CMIP6).
-end-
Pictures Artic sea ice (free download): https://www.cen.uni-hamburg.de/en/about-cen/news/11-news-2020/2020-04-20-sea-ice-notz.html

Contact:

Prof. Dr. Dirk Notz
Universität Hamburg
CEN - Center for Earth System Research and Sustainability
CLICCS - Cluster of Excellence for Climate Research
Phone: +49 40 42838-5337
E-Mail: dirk.notz@uni-hamburg.de

Stephanie Janssen
Outreach
Universität Hamburg
CEN - Center for Earth System Research and Sustainability
CLICCS - Cluster of Excellence for Climate Research
Phone: +49 40 42838-7596
E-Mail: stephanie.janssen@uni-hamburg.de

University of Hamburg

Related Global Warming Articles from Brightsurf:

The ocean has become more stratified with global warming
A new study found that the global ocean has become more layered and resistant to vertical mixing as warming from the surface creates increasing stratification.

Containing methane and its contribution to global warming
Methane is a gas that deserves more attention in the climate debate as it contributes to almost half of human-made global warming in the short-term.

Global warming and extinction risk
How can fossils predict the consequences of climate change? A German research team from Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), the Museum of Natural History Berlin and the Alfred Wegener Institute compared data from fossil and marine organisms living today to predict which groups of animals are most at risk from climate change.

Intensified global monsoon extreme rainfall signals global warming -- A study
A new study reveals significant associations between global warming and the observed intensification of extreme rainfall over the global monsoon region and its several subregions, including the southern part of South Africa, India, North America and the eastern part of the South America.

Global warming's impact on undernourishment
Global warming may increase undernutrition through the effects of heat exposure on people, according to a new study published this week in PLOS Medicine by Yuming Guo of Monash University, Australia, and colleagues.

Global warming will accelerate water cycle over global land monsoon regions
A new study provides a broader understanding on the redistribution of freshwater resources across the globe induced by future changes in the monsoon system.

Comparison of global climatologies confirms warming of the global ocean
A report describes the main features of the recently published World Ocean Experiment-Argo Global Hydrographic Climatology.

Six feet under, a new approach to global warming
A Washington State University researcher has found that one-fourth of the carbon held by soil is bound to minerals as far as six feet below the surface.

Can we limit global warming to 1.5 °C?
Efforts to combat climate change tend to focus on supply-side changes, such as shifting to renewable or cleaner energy.

Global warming: Worrying lessons from the past
56 million years ago, the Earth experienced an exceptional episode of global warming.

Read More: Global Warming News and Global Warming Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.