Where the wind blows, it rains: Arctic warming and wacky jetstream ruins European summers

The dramatic loss of summer sea ice in the Arctic has prompted a lot of research interest in the way that this is affecting weather patterns around the northern hemisphere. The latest contribution is Influence of Arctic sea ice on European summer precipitation, by Dr James Screen of the University of Exeter [PhysOrg]. In this “video abstract”, he explains how reductions in Arctic sea ice affect the position of jetstream — the ribbon of winds winding around the planet that guides weather systems — bringing more summer storms to Western Europe, and a recent run of record-setting wet summers to the UK. But as he points out, the effects are planet-wide:

The impacts are not just over northwest Europe. Actually in the model, what we find is that whilst the sea ice loss increases rainfall over northwest Europe, we actually find drier conditions over Mediterranean Europe. Also the jet steam shifts over North America, which can have implications for the weather there too.

Dr Screen’s study underlines a point that I have been making for some time: rapid climate change is not something theoretical that will happen in the future — it’s happening now and we’re feeling the effects. Warming in the Arctic is driving sea ice loss, and the atmospheric consequences are changing the shape of the weather right round the northern half of the planet.

Also interesting, and also looking at jetstream patterns is Probability of US heat waves affected by a subseasonal planetary wave pattern, in which the authors find that US heatwaves might be predictable 15-20 days earlier than at present by monitoring a particular jetstream wave pattern. [Science Daily]

It’s worth noting that an especially vigorous jetstream directed and helped to intensify the recent huge European storm that hammered the UK, Germany and Denmark, killing 16 people and causing huge amounts of damage. Christopher Burt at WeatherUnderground provides a handy overview of the storm that has four names — St Jude, Christian, Simone and Carmen. The storm centre moved 2,000 km in 26 hours, a remarkable pace of 77 kph.

TDB today: no clue, no plan, no future

There’s a huge gap between the emissions reductions the New Zealand government says it wants to achieve, and what its current emissions trading scheme settings will deliver, according to modelling by the Ministry for the Environment. In this week’s post at The Daily BlogNo Clue, No Plan, No Future — I examine the disconnect between words and actions — and the lack of common sense on display on the government benches. Comments over there, please…

Australia’s burning – again

NSWfiresNASAEO2013294

Smoke from the bush fires burning in the Blue Mountains blows over Sydney in this NASA Earth Observatory image captured yesterday. The scale of the fires and their impact on the skies over Sydney and much of New South Wales is prompting much discussion in Australia about the link between weather, climate warming and wildfires, and bringing international pressure to bear on new PM Tony Abbott’s plans to scrap carbon pricing. Here’s researcher Roger Jones, writing in The Conversation:

We found that fire danger in Victoria increased by over a third after 1996, compared to 1972-1996. The current level of fire danger is equivalent to the worst case projected for 2050, from an earlier analysis for the Climate Institute.

While it’s impossible to say categorically that the situation is the same in NSW, we know that these changes are generally applicable across south-east Australia. So it’s likely to be a similar case: fire and climate change are linked.

This early start to the fire season comes after a year of record warmth in Australia — the hottest summer on record, the hottest 12 month period (to September), and it’s looking odds on that calendar 2013 will be the warmest on record. NSW also had its second warmest winter on record, which helped to dry soils out more than usual. With summer still a month away, the prospect for SE Australia’s fire-prone states looks grim.

For historical background on Aussie bush fires, see this overview from Weather Underground expert Chris Burt, and keep up to date with excellent analysis at The Conversation by following the NSW bushfires 2013 tag.

[Update: For pithy comment, do not miss today’s First Dog On The Moon1. ]

  1. Do something about climate change you disingenuous muppet! []

Something (early) for the weekend: grim forecast for oceans and the roots of denial

Something of a miscellany today, coupled with an open thread, to keep you going during a brief pause in posting. First up: a study published this week in PLOS Biology looks at changes in ocean chemistry, temperature and primary productivity over the next century under two emissions scenarios, and finds that no corner of the ocean escapes untouched. From Science Daily:

“When you look at the world ocean, there are few places that will be free of changes; most will suffer the simultaneous effects of warming, acidification, and reductions in oxygen and productivity,” said lead author Camilo Mora, assistant professor at the Department of Geography in the College of Social Sciences at the University of Hawai’i at Mānoa. “The consequences of these co-occurring changes are massive — everything from species survival, to abundance, to range size, to body size, to species richness, to ecosystem functioning are affected by changes in ocean biogeochemistry.”

It’s been a productive few weeks for Mora: he was lead author on a recent study1 published in Nature that estimated when climate in different parts of the world would move beyond anything experienced in the last 150 years — have a play with this interactive map to find out when your part of the world will move into the unknown. See also Climate Central, Science Daily, and a huge amount of press coverage.

Continue reading “Something (early) for the weekend: grim forecast for oceans and the roots of denial”

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TDB Today: The Inconvenient Neighbours

Over at The Daily Blog today, in a post headlined The Inconvenient Neighbours, I consider the case of the Kiribati man who is claiming refugee status in New Zealand because of the impact of sea level rise on his home island. With the IPCC report suggesting that sea level could rise by as much as a metre this century, it’s surely a sign of things to come…