People who have been watching the extreme weather in the Northern hemisphere might be wondering about the cause and if it might repeat itself. Drought in California, ice in Texas and floods in the UK, all at the same time and all record setting extremes . The cause is the loss of sea ice in the Arctic which is having an affect on the jet stream. A shortened explanation is here http://www.climateoutcome.kiwi.nz/ice-melt.html For a much more detailed explanation watch Jennifer Francis give her presentation. We are down to around four million square kilometres of ice compared with the original eleven million but if we get down to two million we will be in real trouble.
There has been a lot of press about how the temperature has stabalised in the last fifteen years so we don't need to worry about the World getting warmer.
This is clearly misinformation because it is not difficult to see that we are still on an upwards course. The chart on the left shows what a small part of all the heat absorbed by the Earth goes into the atmosphere and the vast majority into the sea. The chart below shows where the surface temperature has paused twice before in 1900 and 1940. In those times there was not the technology or research to explain what happened. When I was young the newspapers reported we were going into the next ice age. Another theory is that the coal smoke in the atmosphere, as the World geared up after the war, cooled the climate.
Current research indicates that the heat is going into the Oceans but we still know very little about what goes on in the depths.
For those adrenaline junkies who want more action in climate change, which may have a progression measured in hundreds of years, watchers can be starved of excitement.
The big action at the moment is in the Northern hemisphere summer where polar sea ice extent and the hurricane and cyclone seasons are just beginning.
Neven's Arctic Sea Ice
http://neven1.typepad.com/blog/ has a crowd source prediction where you are invited to predict the minimum extent, which should be in September. The website is a great source of information on the polar ice region.Hurricanes and cyclones are well covered by Wunderground http://www.wunderground.com/tropical/?MR=1
Where Jeff Masters puts out excellent comments and information on the latest events.
There are a lot of bloggers on both sites so there are plenty of people to exchange views and news with.
After the disastrous decline in the Polar sea ice in 2012 all eyes are on this seasons minimum.
With a historical average minimum of around 15 million square kilometres, last year dipped to 3.5 million. This year we are starting with very thin ice and some areas are deeply fractured so it is not a good start. PIOMAS http://neven1.typepad.com/blog/2013/05/piomas-may-2013.html#more is forecasting a level of 3 million square kilometres which could almost be considered ice free.
If the lack of ice really is having a serious affect on the weather in the Northern hemisphere as has been reported by Jennifer Francis and others then Europe, Russia, China and the USA are going to have a very difficult time. The UK has hardly reached 15C and the USA has deep snow in the centre and hot, dry and windy weather with wild fires in California.
Climate change is not linear and predictable and apparently its not in the distant future either.
Although a short upswing in a graph does not mean its going to keep going in that direction Nasa's sea level monitor shows a marked increase.
There have been several reports on the extra heat entering the deep oceans which will cause heat expansion and this would be the likely cause.
Most of the melting ice is already in the oceans so although that is a major worry its not likely to have such a immediate effect without it being reported.
This web site is supposed to be about New Zealand but events in other countries have profound effects on us both economically and environmentally.
There is much debate on the environmental effect of pumping tar sands from Canada to be refined in Texas but so far I have not heard where this oil is to be processed. The biggest oil refinery plant in the World is at Baytown, Houston and presumably it will handled there. This refinery, like many others, is very close to sea level and with one or two meters of sea level rise in the next ninety years and being in a hurricane area there must surely be some concern about its viability due to the high risk and short operational life.
This map is taken from http://flood.firetree.net/ and the dark blue squares shows where the refinery would be flooded at three meters. A bit more sea level rise and a storm surge and the refinery would be flooded. If the USA had to manage for any period of time without this refinery there would be a severe economic impact as well as the massive environmental mess.
If anybody was thinking clearly about this they would either not build it (favourite) or build a new refinery in Chicago.
It’s a bit early to ‘celebrate’ 400 ppm of CO2 as we are only at 395 ppm but what we should expect is pretty clear. Tim Naith and other scientists from Victoria University, Wellington, who have been involved in the Andrill project, have examined the results other their exploration and can point to what we can expect.
In an outstanding project the team drilled down through the ice, passed through the sea and then deep into the sea bed to recover core samples from the bottom. The material here holds records of the ice flow and temperature through changing climates periods over millions of years.
Detailed examination of the core samples has revealed that the last time the Earth had 400 ppm of CO2 in the atmosphere was four million years ago, the temperature was 3C warmer and the sea level was 12 meters higher. What is uncertain is how long it will take and there are thousands of scientists working on that now. A lot of people want to know.
Could the increased melt water in the Antarctic upset the thermohaline circulation which is the massive ocean currents that move water, nutrients and heat around the World?
The report, published in Nature, by Richard Bintanja, a climate researcher at the Royal Netherlands Meteorological Institute in Utrecht and his colleagues show that enhanced melting of the Antarctic ice sheet — which is losing mass at a rate of 250 gigatonnes yearly — has probably been the main factor behind the small but statistically significant sea-ice expansion in the region.
The most commonly understood part of the Great Ocean Conveyor is where the Gulf Stream becomes heavy with salt, as the fresh water freezes out, and the salt laden water sinks into the Ocean. In doing so it is the pump that drives the system. Al Gore in his film ‘An Inconvenient Truth’ pointed to Greenland as a source of fresh water which could stall the complete system.
Could a similar event happen in the Southern Ocean if the ice shelf starts melting from underneath due to the warmer currents, and the fresh water flows over the salty sea water and freezes instead of the sea water?
This would prevent the salty sea water from freezing and it would not sink to help drive the system.
Over the last few years there has been an increased area of sea ice in Antarctica while at the same time a massive loss of ice in the Northern Arctic region.
The two regions are geographically completely different but even so it has been a puzzle.
A new report by Richard Bintanja, lead author of the study at the Royal Netherlands Meteorological Institute shows that the permanent glaciers in the sea are melting from the bottom. This is caused by warmer sea currents melting the glacier ice and the fresh water released is floating over the colder, more dense, sea water and therefore it is more vulnerable to freezing by the cold winter conditions. This has caused more ice to form.
Scientist, Paul Holland of the British Antarctic Survey has shown that the increased wind speed around Antarctica is blowing the fresh surface ice away from the land and this has caused the ice to spread over a larger area.
Which ever is the dominant factor the sea ice melts in the summer and ultimately will be overcome by a warmer World and the area will start to reduce.
The increased rate of glacier melt has been apparent in Greenland for some years, but I thought we were much safer here in the South.Being part of a wider World, we are not exempt. To learn more go here: http://www.sciencedaily.com/releases/2013/03/130327133707.htm