Climate & Climate Change

The NASA news release is here.

Write up from AccuWeather:

In a news release from NASA Monday, a group of scientists have determined that unusual winds caused the rapid decline (23% loss) in winter perennial ice over the past two years in the northern hemisphere. This drastic reduction is the primary cause of this summer’s fastest-ever sea ice retreat in recorded history which has lead to the smallest extent of total Arctic coverage on record.

According to the NASA study, the perennial ice shrunk by an area the size of Texas and California combined between the winter of 2005 and the winter of 2007. What they found was the Arctic Ocean north of Siberia and Alaska was dominated by thinner seasonal ice that melts faster compared to the thicker ice confined to the Arctic Ocean north of Canada. The thinner ice is more easily compressed and responds more quickly to being pushed out of the Arctic by winds.

“Unusual atmospheric conditions set up wind patterns that compressed the sea ice, loaded it into the Transpolar Drift Stream and then sped its flow out of the Arctic,” said Son Nghiem of NASA’s Jet Propulsion Laboratory and leader of the study. When that sea ice reached lower latitudes, it rapidly melted in the warmer waters.

What about these unusual wind patterns. Well, the article does not go into that too much, but I must believe some of this is due to changes in the Arctic Oscillation (AO) and the North Atlantic Oscillation (NAO) which are large atmospheric circulations which have major impacts on the weather in certain parts of the world.

If you look at the two graphics below, you will notice that both the AO and the NAO have been predominately in the positive phase (red) between 1989-1995 and again from 1999 to current. The positive phase of the (AO) typically leads to milder than normal winters over Scandinavia and Siberia, while colder than normal conditions prevail across Greenland. The positive phase of the NAO again leads to colder conditions over Greenland, while much of the eastern U.S. is warmer than normal in general.

Thanks to Marc Morano for sharing this.

Reported in the Daily Mail today:

Schools must warn of Gore climate film bias

Schools will have to issue a warning before they show pupils Al Gore’s controversial film about global warming, a judge indicated yesterday.

The move follows a High Court action by a father who accused the Government of ‘brainwashing’ children with propaganda by showing it in the classroom.

Stewart Dimmock said the former U.S. Vice-President’s documentary, An Inconvenient Truth, is unfit for schools because it is politically biased and contains serious scientific inaccuracies and ‘sentimental mush’.

He wants the video banned after it was distributed with four other short films to 3,500 schools in February.

Mr Justice Burton is due to deliver a ruling on the case next week, but yesterday he said he would be saying that Gore’s Oscar-winning film does promote ‘partisan political views’. This means that teachers will have to warn pupils that there are other opinions on global warming and they should not necessarily accept the views of the film.

Another one from Luke:

From Australia’s equivalent of the BBC (not a compliment!):

Climate change as much a concern as terrorism: survey

A major survey has found that an overwhelming majority of Australians believe global warming is at least as serious a threat to the nation as terrorism.

Sydney University’s US Studies Centre has released one of the most comprehensive surveys ever undertaken on Australian attitudes to America.

The survey reports that 76 per cent of people believe global warming is now equal to or more serious a threat than Islamic fundamentalism.

That supports another recent report by the Lowy Institute for International Policy which also found that global warming had become the top concern……………………….

Defiinition of a survey or opinion poll:

Method of measuring the effectiveness of propaganda.

Peter Harris provided us with a challenging debate here on this blog where the similarity between the current situation and the 400 kya glacial transition was discussed. I sought more information from Jan Hollan – but some background here first.

So if the present time was really analogous to 400,000 years ago (kya) transition, the advice to the IPCC that no ice age was due for many 10,000s of years would be incorrect and a major concern to humanity.

Augustin et al in Nature 429, 623-628 (10 June 2004) | doi:10.1038/nature02599 discuss 8 glacial cycles from Antarctic ice cores. The transition from glacial to interglacial conditions about 430,000 years ago (Termination V) resembles the transition into the present interglacial period in terms of the magnitude of change in temperatures and greenhouse gases, but there are significant differences in the patterns of change. The interglacial stage following Termination V was exceptionally long—28,000 years compared to, for example, the 12,000 years recorded so far in the present interglacial period. Given the similarities between this earlier warm period and today, our results may imply that without human intervention, a climate similar to the present one would extend well into the future.

Jan Hollan reported here that the first ever pronounced fall of summer insolation happens some 130 thousands years from now, but it is not at all so deep as those ones that started the last two Ice Ages. So, we can say there is no conceivable cause for another glaciation for at least those 130,000 years. Quite probably, another glaciation cannot come sooner that 620 thousand years from now.

Berger and Loutre argue in their Science paper that with or without human perturbations, the current warm climate may last another 50,000 years. The reason is a minimum in the eccentricity of Earth’s orbit around the Sun.

There are three interacting aspects of the Earth’s orbit that need to be accounted for in making the Milankovitch radiation calculations – discussed here. The mechanisms are orbit eccentricity (roundness to elliptical); obliquity (axial tilt) and precession (wobble around the axis).

The calculations of solar radiation at 65 degree North from Milankovitch mechanisms are based on a derivative of Laskar et al.

Jan Hollan now provided an additional graph from 500,000 years ago to 200,000 years from present.

Made for a rather low 1366.3 W/m2 solar constant again. -400 ka summer insolation minimum was some 10 W/m2 lower than that one we have almost reached already. No pronounced decline of solar orbital summer forcing at 65° N is ahead of us next 50,000 years. Jan Hollan suggests we should not extrapolate past trends (like decline in summer insolation, or the shape of the past glaciation cycles). We should look at reliably computed past, current and future forcings instead (see Laskar et al for the mathematics involved). Hollan states that it is evident we have almost reached the near-future insolation minimum already. Before the atmosphere returns to normal (thousands of years), we will be on the increasing part of the insolation curve again.

Which all means – no Milankovitch based ice age predicted for 50,000 years and more likely 130,000 or 620,000 years hence according to Jan Hollan.

From Marc Morano:

The Cryosphere Today

UPDATE: Monday, October 1, 2007 – Record SH sea ice maximum and NH sea ice minimum

Just when you thought this season’s cryosphere couldn’t be more strange …. The Southern Hemisphere sea ice area narrowly surpassed the previous historic maximum of 16.03 million sq. km to 16.17 million sq. km. The observed sea ice record in the Southern Hemisphere (1979-present) is not as long as the Northern Hemisphere. Prior to the satellite era, direct observations of the SH sea ice edge were sporadic.

The NH sea ice area reached an historic minimum on September 16, 2007 (2.92 million sq. km), representing a 27% drop in sea ice coverage compared to the previous (2005) record NH ice minimum.

We have updated our high resolution animation of this year’s sea ice retreat (01/01/2007 – 09/23/2007). WARNING – This quicktime animation is very large at 200Mb, but it illustrates nicely the temporal evolution of this year’s sea ice. Animation: 2007 sea ice minimum animation

Follow this link for some background information on historic sea ice minima.

Also note that Antarctic is NOT following climate models.

A February 2007 study reveals Antarctica is not following predicted global warming models. Excerpt: “A new report on climate over the world’s southernmost continent shows that temperatures during the late 20th century did not climb as had been predicted by many global climate models.” The research was led by David Bromwich, professor of professor of atmospheric sciences in the Department of Geography, and researcher with the Byrd Polar Research Center at Ohio State University. [See: Antarctic temperatures disagree with climate model predictions]

Reply to Lockwood and Fröhlich – The persistent role of the Sun in climate forcing

Svensmark, H. and Friis-Christensen, E.
Danish National Space Center, Copenhagen, Denmark

In a recent paper (ref. [1]) Mike Lockwood and Claus
Frohlich have argued that recent trends in solar climate
forcing have been in the wrong direction to account for
“the observed rapid rise in global mean temperatures”.
These authors accept that “there is considerable evidence
for solar in°uence on Earth’s pre-industrial climate and
the Sun may well have been a factor in post-industrial
climate change in the first half of the last century.” But
they argue that this historical link between the Sun and
climate came to an end about 20 years ago. Here we
rebut their argument comprehensively.

pdf here.

By Lockwood and Frohlich’s own data, solar magnetic
activity is still high compared with 100 years ago. As
to when the recent easing of activity began, counts of
cosmic-ray muons at low altitudes were historically low
when the muon record-keeping ended in the early 1990s
(ref. [7]). That implies an increase in relevant solar mag-
netic activity continuing till that time. A scarcity of
muons can be linked to elevated global temperatures by a
reduction in low cloud cover (ref. [8]) and low cloudiness
was indeed at a minimum around 1992-93. By other so-
lar indicators, like those cited by Lockwood and Frohlich,
the minimum muon counts may well be a little higher in
the current solar cycles. That would explain the pause in
global warming evident in our Table as well as in Lock-
wood and Frohlich’s own Fig. 1e.

That would explain the pause in global warming ev-
ident especially in the ocean (Fig. 1) and the tropo-
sphere (Fig. 3). The continuing rapid increase in carbon
dioxide concentrations during the past 10-15 years has
apparently been unable to overrule the flattening of the
temperature trend as a result of the Sun settling at a
high, but no longer increasing, level of magnetic activity.
Contrary to the argument of Lockwood and Frohlich, the
Sun still appears to be the main forcing agent in global
climate change.