Science

A recent study looking into regional tropical cyclone formation conditions in the east and central Pacific has projected that 2 to 3 times more tropical cyclones (Hurricanes) are likely to hit Hawaii in the later part of this century.

James Ross island, Antarctic PeninsulaThis study analysing an Antarctic Peninsula ice core from James Ross island has determined that there has been a ten fold increase in melt intensity over the last 600 years. I reported recently that the Antarctic Peninsula summer melt season prolonged by global warming according to research from the British Antarctic Survey.

"The warming has occurred in progressive phases since about AD 1460, but intensification of melt is nonlinear, and has largely occurred since the mid-twentieth century. Summer melting is now at a level that is unprecedented over the past 1,000 years. We conclude that ice on the Antarctic Peninsula is now particularly susceptible to rapid increases in melting and loss in response to relatively small increases in mean temperature." concludes the study.

It seems the genetics of the Antarctic Octopus is showing us how fragile the West Antarctic Ice sheet (WAIS) may be with global warming. It raising questions about the ice sheet susceptibility to collapse.

NASA image: Rossby Waves of the JetstreamA series of major extreme weather events in the Northern hemisphere including the heatwave in the United States in 2011, the Russian heatwave of 2010, the Pakistani floods of 2010 have now been attributed to a common physical cause. The scientists suggest in a new scientific study that man-made climate change repeatedly disturbs the patterns of atmospheric flow - the atmospheric Rossby waves of the jet stream - around the globe's Northern hemisphere through a subtle resonance mechanism.

"An important part of the global air motion in the mid-latitudes of the Earth normally takes the form of waves wandering around the planet, oscillating between the tropical and the Arctic regions. So when they swing up, these waves suck warm air from the tropics to Europe, Russia, or the US, and when they swing down, they do the same thing with cold air from the Arctic," explains lead author Vladimir Petoukhov.

At what point might we trigger a permafrost tipping point? New research from the caves of Siberia points to a threshold temperature of just 1.5 degrees celsius. At that temperature we could see large swathes of permafrost across Siberia melting resulting in the release of more than 1,000 gigatons of carbon and methane. This would be a substantial climate feedback resulting in even greater global warming. There would also be substantial damage to natural and human environments and structures.

And we are already halfway there to warming the world by 1.5C, with an estimated global temperature rise since the Nineteenth century of between 0.7 and 0.8 degrees C. There is already enough inertia in the climate system to carry us over this threshold. Which makes every attempt to reduce carbon emissions, and the use of fossil fuels, as worthwhile to limit the permafrost thaw.

Related: Methane and CO2 in thawing Arctic permafrost a climate tipping point | "We do have an emergency" - Arctic Methane Feedback amplifying warming | Arctic Permafrost thawing raising CO2 levels

Labour capacity reduced due to heat stress as temperature and humidity rises with Climate ChangeClimate change will result in hotter and more humid environment for the tropics and mid latitudes resulting in increasing economic costs of reduced work capacity due to heat stress. The study by NOAA scientists said work capacity has already reduced by 10 percent due to extreme heat in summer months. This is likely to double to 20 per cent by 2050.

One of the physical properties of warmer air is that it can hold more moisture. So in hot weather atmospheric humdity can be more extreme. But there are physiological limits of human health in coping with temperature extremes. In 2010 Scientists outlined health limits of heat stress with Climate Change. The scientific paper by Steven Sherwood from the University of NSW and Professor Matthew Huber from Purdue University - 'An Adaptability Limit to Climate Change Due to Heat Stress' outlined the health adaptation limits of the human body.

A worldwide review of global rainfall data led by the University of Adelaide has found that the intensity of the most extreme rainfall events is increasing across the globe as temperatures rise.

The diminishing Arctic sea-ice extent is resulting in changes in how greenhouse gases interact between the land, ocean and atmosphere according to a new study.

"Changes in the balance of greenhouse gases can have major consequences because, globally, plants and the oceans absorb around half of the carbon dioxide that humans release into the air through the use of fossil fuels. If the Arctic component of this buffer changes, so will the amount of greenhouse gases in the atmosphere", says Dr Frans-Jan Parmentier, a researcher at Lund University, Sweden, and lead author of the study.

Greenland Ice Mass change rate 2012Climate scientist James Hansen and his colleague Makiko Sato have released a new discussion paper with updated data on ice sheet mass loss from Greenland and Antarctica, with implications for possible multi-metre sea level rise this century. It makes for some interesting reading - there is a link to Hansen's website and the paper at the end.

The thesis that Hansen has put forward for several years is that Ice Sheet collapse is a non-linear process: that with the inclusion of amplifying climate feedbacks it is likely to follow an exponential rate of acceleration - a doubling rate. It might be a 10 year doubling time, or less. This will lead to extensive sea level rise, perhaps in the order of 5 metres this century.

Related: Matt Owens on Direct impacts to US GDP: that direct losses could top 1/4 trillion per year during 2040-2050

Original article from San Fransisco Bay Area Indymedia, Dec 23rd, 2012 7:16 PM: The West Antarctic Ice Sheet is warming at three times the global average, according to temperature measurements at Byrd Polar Station. This has implications for the melting of the West Antarctic Ice sheet (WAIS) and sea level rise.