For the Arctic, like the globe as a whole, 2016 has was extraordinarily warm. For much of its first year, Arctic temperatures have been much higher than normal, and ocean frost concentrations have been at record low levels.
The Arctics seasonal cycles/second means that the lowest ocean frost concentrations occur in September each year. But while September 2012 had less frost than September 2016, this year the frost coverage has not increased as expected as we moved into the northern winter. As a make, since late October, Arctic sea ice extent has been at record low levels for the time of year.
NSIDC, Author provided
These record low ocean frost tiers have been associated with exceptionally high temperatures for the Arctic region. November and December( in so far) have insured record warm temperatures. At the same hour Siberia, and very recently Northern america, have suffered healths that are somewhat cooler than normal.
Geert Jan van Oldenborgh/ KNMI/ ER-AInterim, Author provided
Extreme Arctic warmth and low-pitched frost coverage affect the migration motifs of marine mammals and have been linked with mass starvation and deaths among reindeer, as well as affecting polar bear environments.
Given these severe ecological impacts and the potential influence of the Arctic on the climates of Northern america and Europe, it is important that we try to understand whether and how human-induced climate change has played a role in this event.
Our World Weather Attribution group, led by Climate Central and including researchers at the University of Melbourne, the University of Oxford and the Dutch Meteorological Service( KNMI ), expended three different methods to assess the role of the human climate affect on record Arctic warmth over November and December.
We used forecast temperatures and hot perseverance simulates to predict what will happen for the rest of December. But even with 10 periods still to go, it is clear that November-December 2016 will certainly be record-breakingly warm for the Arctic.
Next, I investigated whether human-caused climate change has altered the possibilities of particularly warm Arctic temperatures, employing state-of-the-art climate simulates. By likening climate model simulations that include human affects, such as increased greenhouse gas concentrations, with ones without these human effects, we can estimate the responsibilities of climate change in this event.
Andrew King, Author provided
To put it simply, the record November-December temperatures in the Arctic do not happen in the simulations that leave out human-driven climate ingredients. In happening, even with human effects included, the simulates suggest that this Arctic hot spell is a 1-in-200-year phenomenon. So this is a freak phenomenon even by the standards of todays world, which humans have warmed by roughly 1 on average since pre-industrial times.
But in the future, as we continue to emit greenhouse gases and further warm countries around the world, happenings like this wont be freaks any more. If we do not reduce our greenhouse gas radiations, we estimate that by the late 2040 s this event will occur on average formerly every two years.
Watching current trends
The group at KNMI expended observational data( not a straightforward task in an area where very few remarks are taken) to investigate whether the likelihood of extreme heat in the Arctic has changed over the past 100 years. To do this, temperatures somewhat further south of the North Pole were incorporated into the analysis( to make up for the lack of data all over the North Pole ), and these indicated that the current Arctic heat is unprecedented in more than a century.
The observational analysis reached a similar conclusion to the model survey: that a century ago this event would be extremely unlikely to occur, and now it is somewhat more likely( the observational analysis sets it at about a 1-in-50-year phenomenon ).
The Oxford group expended the very large ensemble of Weather @Home climate model simulations to liken Arctic heat like 2016 in the field covered by today with a year like 2016 without human affects. They also found a significant human affect in this event.
All of our analysis times the finger at human-induced climate change for this event. Without it, Arctic warmth like this is extremely unlikely to occur. And while its still an extreme phenomenon in todays climate, in the future it wont lies in the fact that unusual, unless we drastically curtail our greenhouse gas emissions.
As we have already seen, the results of more frequent extreme warmth in the future “couldve been” destroying for the animals and other species that call the Arctic home.
Geert Jan van Oldenborgh, Marc Macias-Fauria, Peter Uhe, Sjoukje Philip, Sarah Kew, David Karoly, Friederike Otto, Myles Allen and Heidi Cullen all contributed to the research on which this article is based . em>
You can find more details on all the analysis techniques here. Each of the methods used has been peer-reviewed, although as with the Great Barrier Reef bleaching study, we will submit a research manuscript for peer review and publication in 2017.