Snow, that website was last updated "1635 GMT, 15th Aug 2008" so is a little outdated. If you compare the graph below from your quoted website with the one that Em has posted above you will see that your quoted author has been selective in his choice of date range and that after that date range there is a considerable decline in ice area. When the later data is added it is clear that the date range whcih he has printed is part of a decline curve.
I have here quoted an article which asks why CC deniers do not publish there papers for peer review in journals.
This pie chart shows the number of Climate Scientists who published reports denying AGW
Perhaps you could give a reason why so few papers are published in reputable journals by relevant scientists talking against CC/GW. To me it is instructive that the main protagonists against CC/GW in the UK are journalists, historians and economists, non of whom are true scientists, i.e. their discipline doesn't require the publication of peer reviewed papers to advance their theories. They just don't understand the scientific method and the rigor with which scientific theories are examined before acceptance.
Snow, in the graph above your man is telling us that ice area was constant in the period 79 to 99 but in the graph but in his fig. 15 he is telling us that it should be melting. Just another inconsistency. If I read the whole lot how many more would I find?
Can't you find a more recent source? John L Daly died in 2004 and the article obviously predates his death!!
Sea ice extent is not the most representative measure of sea ice. It is used because it is the easiest to measure, and shows least short term variability. Sea ice volume is the moist important figure if whilst rapid melt is happening, and this has shown a sixty to seventy percent fall at summer minimum, and a large fall at winter maximum, in the L ast thirty years. There is no evidence of anything like that for millions of years in old ice studies.
snow hope wrote:Rather than just looking at a 30 year time scale it would probably help to look at longer time scale. Going back to 1817 shows an interesting piece of information - do you think global warming started back then?
And please read the article rather than put forward straw man arguments....
It's worth checking out the gaps in that 1817 quote. These kinds of data points are useful to an extent but they don't give a complete picture by any stretch of the imagination (and let's not forget the ability of sailors to exaggerate...). And this was in the *very* early days of arctic exploration.
The extent of arctic sea ice fluctuates a lot from year to year so it's entirely possible that areas of ice that had previously been closed off would open up sometimes:
The stalled jet stream of the last two months, the massive arctic dipole pushing the arctic old out of the arctic and into the US, and possibly other factors, has resulted in very warm weather up north. The heat wave in Alaska is finally over, but further north is still 20C above seasonal norm (at -15C).
This has resulted in a stalled ice growth season. Currently, both area and extent measurements are at record low for this time of year, 6 weeks before annual maximum. Volume is still up 14% on last year, but that figure is sure to decline in next month's figures.
If this weather pattern persists (and this seems likely for at least a week) then we could see very rapid melt on the Atlantic side of the arctic basin, with the possibility of the North Pole being ice free by September.
The thicker ice that is in the Barents Sea (relative to recent years) may hold out if we get another cool cloudy summer, but if we get lots of stable high pressure systems like 2012 then that too will melt out, and all of last year's recovery will be gone.
As always, time will tell.
The antarctic is very cold. Sea ice is well above long term average, and has been for a couple of years now. Opinions vary as to the cause, some say it is caused by land based ice flowing to the sea faster.
The February ice volume data is out. As expected most of last year's "recovery" of ice volume has not been sustained. Less than a quarter of that recovery remains. Annual maximum is reached in 4 to 6 weeks.
Both extent and area measurements are tracking at or very close to record lows. It is possible that the annual maximum for these has already passed, but colder weather is expected for the next few days, (balancing the warmer weather here) so it is too early to call.
It is, however, clear that last year's recovered was a weather based blip, and the trend to total melt-out has been delayed by 2 years at most. A strong El Nino year could see another year of record ice loss.
Another month over, and sea ice has now passed annual maximum extent and area. Values are middle of the pack for the last few years, as they reflect weather more than climate at the maxima.
There is growing evidence of a strong to very strong el-nino event this year, where heat which has been building up in the oceans the last few years (leading to denialist claims of global warming having stalled) is released back into the atmosphere.
We are likely to see new record global temperatures again this year, on past record this will be followed, either this year or next, by record arctic ice melt.
Volume at peak was back very close to record lows, showing that the recovery was merely weather.
However, one possible interpretation of last year's weather is that we are beginning to see some negative feedback slowing the final demise of the ice. All through summer the arctic air temperatures were below normal, and cloudy weather dramatically cut the rate of ice melt in the late may/early june period which appears to be a strong indicator of total ice volume at minimum.
The theory goes that the very thin and fractured nature of the ice is causing the humidity of the air to rise sharply at this time of year, as open water in the cracks evaporates far more quickly than the cold ice itself. This is leading to cloudy weather, less direct sun and slower melt.
So far this year, the pattern is similar to last year. The warm winter has lead to thin, fractured ice, and in the last two weeks the weather has again flipped from warmer than trend to cooler, delaying melt at the critical period.
Long range weather forecasting in the arctic beyond about 4 days is just about useless, so the weather in next few weeks will have a big impact on the final summer melt.
The core arctic remains stubbornly frozen, averaging about -4C air temperature, about 4 degrees below normal. Normally large areas of melt ponds form on the surface of the ice at this time, reducing the albido and accelerating melt. This hasn't happened yet. To some extent this may be because the ice is now so thin and fractured that most of the melt ponds drain through to the ocean below.
However, the sea surface temperatures of the open water around the arctic are widely 2C above normal for the time of year, strongly suggesting something. It takes a lot more heat to raise water by 2C than it does to raise air by 4 degrees.
Also, an area of open water as large as the UK has opened up on the Siberian side of the arctic, very unusual this early in the year. It seems the sun's heat is going straight into the water and bypassing the ice.
Finally high pressure, clear skies and sunshine have hit the central arctic just in time for the solstice and peak melt rates. Forecast is to stay that way at least for a few days, and the ice is melting fast.
Still the onset of rapid melt is 2 weeks later than the previous record year of 2012, and it is very difficult to forecast the unprecedented.
El Nino is beginning to show classic sea surface temperature profile, and May was a global air temperature record.
My personal suspicion is that clouds will return and prevent record ice melt, just as they seem to be dominating weather here in Cambridge. Warmer air over the oceans causes more cloud formation, and the wind has to blow them somewhere.
Well, 5 five days of rapid ice melt and the weather forecast is for more of the same.
A long way to go yet, but it is looking a lot less likely that this year will be anywhere close to last year's rebound. The ice now has plenty of melt ponds over wide areas of the arctic, and being lower albido means they form a short term positive feedback. Once they form, they don't freeze again even if the weather turns cooler, and there is little evidence that it will, although the high arctic is still struggling to get above 0C.
