As I pointed out in the Antarctica post, this coincides to: http://climate.gi.alaska.edu/ResearchProjects/Hartmann%20and%20Wendler%202005.pdf

and

http://icecap.us/images/uploads/More_on_The_Great_Pacific_Climate_Shift_and_the_Relationship_of_Oceans_on_Global_Temperatures.pdf

and

http://www.nasa.gov/vision/earth/environment/PDO.html

I wish it would widen up here!!! I AM FREEZING!!!!....

Pittsburgh Weather. Proof that Global Warming is a CROCK!!!!!!!

widening of the tropics by several degrees latitude since 1979

Wasn't 1979 the year climatologists were in a panic about global cooling?

According to Hansen's unbiased GISS data, temperatures in the tropics have increased by a whopping 0.3 degrees since 1979. Scary stuff.
http://data.giss.nasa.gov/cgi-bin/gistemp/do_nmap.py?year_last=2007&month_last=10&sat=4&sst=1&type=trends&mean_gen=0112&year1=1979&year2=2006&base1=1951&base2=1980&radius=250&pol=reg

the Earth's tropical belt (area between the tropic of Cancer and the tropic of Capricorn) has widened over the past 25 years

The Tropic of Cancer is where the sun is directly overhead during the NH summer solstice and the Tropic of Capricorn is underneath the NH winter solstice. Apparently global warming is now affecting the orbit and tilt of the earth too.

Perhaps the AGW belts are widening from excess funding?

Maybe the Earth is just getting a little tubby in its' old age, get it, bulging belly stretching the belt...

Ok, I'll go back to my day job.

Have to wonder if the change is being identified rather as our definition of tropical climates has changed rather than an actual heat thing.

Nevertheless, seems like a decent thing to me.

One question?. What are all those colors supposed to mean and how much dta is it based off?

Global warming hits Montreal - hard.
http://nationalpost.com/news/story.html?id=141305

"I heard somebody say that it might never snow again ..... I'm sick of politicians refuting global warming "
http://bushiki.spaces.live.com/blog/cns!F30919C60BA02E6!401.entry

Brett, it's not entirely clear from your phrasing, but you may have misunderstood an important nuance: While many of the implications of the expansion for the rest of the climate system aren't yet clear, that the expansion is being driven by warming very much is. In other words, the warming (the primary cause) affects all of the things you listed (the mechanisms), some or all of which in turn drive the expansion (noting that there may also be a degree of natural variability). The paper itself is here for those who might want to see the details. The abstract:

"Some of the earliest unequivocal signs of climate change have been the warming of the air and ocean, thawing of land and melting of ice in the Arctic. But recent studies are showing that the tropics are also changing. Several lines of evidence show that over the past few decades the tropical belt has expanded. This expansion has potentially important implications for subtropical societies and may lead to profound changes in the global climate system. Most importantly, poleward movement of largescale atmospheric circulation systems, such as jet streams and storm tracks, could result in shifts in precipitation patterns affecting natural ecosystems, agriculture, and water resources. The implications of the expansion for stratospheric circulation and the distribution of ozone in the atmosphere are as yet poorly understood. The observed recent rate of expansion is greater than climate model projections of expansion over the twenty-first century, which suggests that there is still much to be learned about this aspect of global climate change."

Note the emphasis on the consequences for the subtropics. These regions are where the big deserts are located, and we really don't want those deserts to shift poleward into presently fertile areas. The Australians, already suffering from the worst drought in their history, have put two and two together:

'The director of the Research Institute for Climate Change and Sustainability at the University of Adelaide, Barry Brook, said it would push the westerly systems that bring rain to Australia's southern coast closer to the South Pole.

'"As they shift southwards, progressively more rain is dumped over the Southern Ocean, instead of over continental Australia, where we need it," he said. The expanding tropics would also extend the range of tropical diseases, Professor Brook said.

'"Subtropical cities such as Brisbane, and even those that are currently only marginally subtropical, like Sydney, will become increasingly suitable for diseases such as dengue fever, Ross River virus and perhaps eventually malaria."

'He said the findings, published in the journal Nature Geoscience, were another sign that climate change was occurring sooner than expected and made the case for rapid action on greenhouse gas emissions much more compelling and urgent.'

"Yawn".

Another nonstory as I pointed out with the proposed changes to the growing zones chart that was supposed "evidence". Look back at that one, the "new" chart was generally a return to the original chart, which had been adjusted southwards for the "Ice Age" AGC event of the 70s.

So, do they have any records from before the 70s? Are the tropics just returning to where they were then?
Is taking a start point at about the end of the last big cooling cycle honest or skewing the data?
Especially since using 1998 as a start year is supposed to "skew" the data so it shows a cooling?

Mr. Bllom,

In response to: "These regions are where the big deserts are located, and we really don't want those deserts to shift poleward into presently fertile areas." You seem to imply that the major subtropical deserts are expanding.

I expect, much to your chagrin, that the following must be somewhat upsetting to you, then:

But vegetation measurements collected every day by U.S. meteorological satellites show that the southern edge of the Sahara ebbed and flowed more like a tide over an 11-year period starting in 1980. Compton J. Tucker and Wilbur W. Newcomb of NASA's Goddard Space Flight Center in Greenbelt, Md., and Harold E. Dregne of Texas Tech University in Lubbock report the observation in the July 19 SCIENCE.

"The message [of these results] is that a lot of what's been claimed about the so-called desertification of the Sahel is just incorrect," says Sharon E. Nicholson, a meteorologist at Florida State University in Tallahassee, who has studied rainfall patterns in Africa.

My favorite part is the highlighted 11-year period. That time frame sounds vaguely familiar.

"We looked at how certain aspects of the structure and circulation of the atmosphere have been altered over the past few decades and how models predict they may change as the climate changes in the future,� said Dian Seidel, lead author and research meteorologist with NOAA�s Air Resources Laboratory in Silver Spring, Md. �We are seeing indications that a warming climate is associated with expansion of the tropical region toward the poles,"

Not a very confident study. And if one considers that there has yet to be an AGW footprint in the tropical tropesphere, one can pretty much dismiss this "study" as pure nonsense.

What??? This is the biggest crock ever.

The only way the tropic belt can grow is if the earths axis changes??? Not to mention that would only shift the belts in the same direction and not repel each other. I think these scientists need to say "tropical weather patterns shift several degrees from equator". The tropic belt has nothing to do with weather or temperature but the movement of the earth. Am I wrong? I don't think so... 23.5 degrees is the tropic line and global warming can't change that because it has nothing to do with earths TILT

if seas are warming (goes back six month trend)
http://www.osdpd.noaa.gov/PSB/EPS/SST/data/anomnight.12.3.2007.gif
and ice is melting (notice its back to 0 and winter just started up there NH)
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/global.daily.ice.area.withtrend.jpg
and temperatures are rising (seem to be declining)
http://vortex.nsstc.uah.edu/data/msu/t2/tmtglhmam_5.1
who is telling the truth. This data is not consistent with above proposition

Look back at that one, the "new" chart was generally a return to the original chart, which had been adjusted southwards for the "Ice Age" AGC event of the 70s.

Kamatu, do you have some references (other than Newsweek magazine and some contrarian talking-point memos) to support your contention that the "original chart" "had been adjusted southwards for the 'Ice Age' AGC event of the 70s" (I presume your "southward" refers to the northern boundary)?

I'm very interested in seeing a link to one of these southward "adjustments" to these alleged "original charts".

It is about time that science confirmed what common sense tells us. As global warming widens the tropics, boils the seawater off, more very difficult to measure humidity occurs, and becomes readily visible rain & snow. And as I mentioned earlier, all that cooling of the Artic melting has to go somewhere. It seems to have hit Pittsburgh particularly hard, according to our friend Oiznop above:

I wish it would widen up here!!! I AM FREEZING!!!!....
Pittsburgh Weather. Proof that Global Warming is a CROCK!!!!!!!
Posted by Oiznop | December 4, 2007 3:39 PM

Thanks, Dave Schneider
Million miler US Trucker/Weather Watcher

Why do the Heidi Cullens-like fear mongers at the Weather Channel continue showing Canada as being GREEN on their weather maps? They show the northern arctic as being white. Canada is now freezing and buried under snow. Therefore their map of Canada should be accurately represented as being white, not global warming green. Intentional? Just an observation.

Lawnmowers causing global warming.

http://www.townhall.com/video/FoxLocal/2095_0902PushMower1

What were the atmospheric CO2 levels when this new found creature lived 150 million years ago?

http://www6.comcast.net/news/articles/science/2007/12/04/Norway.Prehistoric.Reptiles/?cvqh=ht_seamonster

Really how can the tropical belt expand when that would mean the equator would move too?

Those colors puzzle me too. I tend to think it is to make the map look pretty and pleasing to the eyes.

Guys,

This paper is not saying that the geographical tropic belt is moving. Obviously, that definition of tropics is based on the axial tilt of the earth and would be the same if the earth is in an ice age. They are talking about climatic belts.

From: http://books.nap.edu/openbook.php?record_id=11798&page=155

The early Eocene appears to represent the warmest part of the Tertiary. The marine record in the North Atlantic, as well as elsewhere, indicates that the most poleward (50�55� N) excursion of low-latitude assemblages occurred at this time; the tropical-subtropical belt may have been double its present latitudinal extent.

The links I gave refer to a shift from a negative PDO to a positive PDO in the mid 70's. "The Pacific Decadal Oscillation index shifted in 1976 from dominantly negative values for the 25-yr time period 1951�75 to dominantly positive values for the period 1977�2001." Is the "expanding tropics" since 1979 a result of the change in PDO?

On a side note my belt line has been widening lately too. Can I tell my wife that's because of global warming?

More desperate and irrelevant flopping around from the denialists. Paul amuses by getting the location of the expected desertification completely wrong. Hint: It's the poleward edges of the subtropics that we're worried about. Don't ever change, Paul.

SM: My question was really whether you had read and understood the material you linked. Thanks for answering it.

yes but thats' a natural cycle and not caused by man in any way,at least directly.

Seems to me that NFL football rules are applicable here. A play occurs, and the refs make a call. If the opposing team disagrees with the call, the refs examine all the available film, and reassess their initial call. Only with irrefutible evidence is the original call overturned.

The analogy is this.

The play is the climatological history of the earth. The call is "natural cycles", not so long ago, and therefore now, by reason of continuity in the laws of nature. The opposing team -- the AGW alarmists -- object to the call. A reassessment occurs. The "film" is the present re-examined in light of climatological history. There is no irrefutable evidence against the original call, nothing that definitively proves AGW. In fact, "the film" shows definitive evidence against AGW (e.g., the absence of a large delta between surface and lower tropospheric temps). The call stands. Natural cycles, not AGW.

Hint: It's the poleward edges of the subtropics that we're worried about. Don't ever change, Paul.

That's curious. Now you say that you're not worried about desertification towards the equator? If that's the case, I am truly surprised, Mr. Bllom.

The equatorial march of the Sahara from the north and the northward expansion of the Kalahari from the south would result in the complete desertification of the entire continent of Africa. And that doesn't concern you, Mr. Bllom?

Considering how often the AGW zealots are wrong, I'm somehow supposed to believe that Mr. Bllom is correct in his assumption that only poleward desertification will take place. Actually, I would be willing to place a bet that the deserts will pretty much stay the same with minor fluctuations at the edges for quite some time. However, all bets are off in case of major volcanic eruptions (not little Pinatubo or St. Helens type eruptions, but major caldera-forming eruptions, ie., Yellowstone) or major tectonic shifts.

Travis, hot off the press and just for you.

ScienceDaily (Dec. 4, 2007) - Finally, some good news about the prospects of coral reefs in the age of climate change. According to a new study by the Wildlife Conservation Society, corals may actually survive rising ocean temperatures....

http://www.sciencedaily.com/releases/2007/11/071129183829.htm

Corals evolved at 7000ppm CO2.

Patrick,

Thanks for the link. I think it illustrates my point about evolution and adaptation quite nicely:

Researchers discovered that coral reefs in sites with varying seasonal temperatures are more likely to survive the 'hot pulses' of Climate Change. Conversely, reefs living in environments with stable but higher temperatures are more susceptible to "bleaching," a global phenomenon where beneficial algae are "evicted" by corals, ultimately leading to the reef's demise.

The researchers also discovered that the coral reefs in sites with the most temperature variation were in the 'shadow' of islands, protected from the oceanic currents that reduce temperature variations in reef ecosystems. According to the authors of the study, the results suggest that corals in these locations are better adapted to environmental variation. Consequently, they are more likely to survive dramatic increases in temperature.

Coral species that have adapted well to change are the ones that will flourish. The ones that have not will become extinct. Evolution happens the same way now as it has for the past bi