11 August 2007

Global Warming and Climate Change,
Part 0: Alarms (and Alarmists)

Primary sources:
4 August 2006: Washington Post
More Frequent Heat Waves Linked to Global Warming
7 February 2007: People's Daily Online
Global warming results in extreme weather events in China
25 July 2007: Chicago Sun-Times
Higher city temps blamed on global warming
7 August 2007: UN World Meteorological Organization
Press Release No. 791
8 August 2007: the daily green
U.N.: Extreme Weather Is Sign Of Global Warming
9 August 2007: Planet Ark (Reuters)
INTERVIEW - Asia Floods Show Climate Change Risks Ahead
9 August 2007: Planet Ark (Reuters)
ANALYSIS - Floods Find India Wanting as Climate Change Looms
Additional sources include Wikipedia.

Following a new UN report and press release on the already-apparent impacts of global warming on weather events and daily lives around the world, the daily green (listed above) offered some "facts" on global warming:
  • Eleven of the past twelve years rank among the 12 warmest on record for global surface temperature.
  • The rate of warming has doubled in the past 50 years.
  • The temperatures in the Northern Hemisphere in the second half of the 20th century were very likely higher than any other 50-year period in at least 500 years, and likely the highest in at least 1,300 years.
  • Extreme weather events have become more frequent in the past 50 years.
  • Unabated global warming will continue to make extreme weather events more frequent.
Let's pick this list apart, shall we? The first two items can indeed be considered "facts" of global warming, as they are based on hard data and scientific analysis. The third item is conjecture (note the language: "very likely" and "likely"), based on available evidence that is far smaller in volume than the most recent records. The fourth item is subjective, and depends entirely on how "extreme weather events" are defined. The last item isn't a "fact" but rather a prediction, or more precisely a hypothesis (educated guess).

I plan to address various aspects of global warming, a.k.a. climate change, in several posts on the topic. Right up front, note that I'm not at all a skeptic on the issue of global warming--the statistical evidence is obvious and well-founded. I read Al Gore's Earth in the Balance way back when it was published the first time, in 1992, and I've been a scientist-philosopher and tree-hugger (or maybe "water-hugger," to coin a term) ever since. A few things are clear to me by now: (1) the data and interpretations of global warming and climate change are constantly subject to manipulation and obfuscation, (2) we can't reverse global warming, and (3) we can't "save the Earth," but we can work really hard to "save the humans."

On the first point, I need only to point out that the American Association of Petroleum Geologists (AAPG) is one of the few professional scientific organizations that still does not endorse the most authoritative reports from the Intergovernmental Panel on Climate Change (IPCC). To be clear, those are scientists in a professional association oriented on Earth Science, and they still doubt, which is certainly their right and responsibility--where would science be without doubt? My guess is that the AAPG is simply more susceptible to manipulation at the highest levels by political and commercial interests. Politicians and bureaucrats in our own federal government, some of whom are closely tied to (and even still employed by) the massive oil industry, have relied on threats and deception to deny public access to information and to alter public opinion, primarily to advance their own agendas and profits, and they are beyond contempt.

What do I really think about them? They should all spend a summer in Iraq as laborers, working the oil wells that they so dearly want to exploit and getting shot at while they do it. Then, when they get some time off, they should go to India and Bangladesh to assist relief efforts following the monsoon and cyclone floods. For the winter, they should go to Africa to build houses and drill water wells in increasingly dry conditions, where they just might get shot at again while they're working to protect refugees from the genocide in Darfur. But enough about my disdain for corrupt politicians and their meddling with the scientific process...

On the second point, apparently there's so much heat trapped in the oceans by now that, even if we cease all carbon and other greenhouse emissions immediately, the warming trend would actually continue for another thousand years or so before a new quasi-stable climate is established. In the meantime, the Earth's systems are always in a dynamic balance. One little change in the atmospheric greenhouse gas content will cause higher surface temperatures, melt ice caps, slow the ocean circulations, enhance the intensity of the atmospheric hydrologic cycle, bring on more extreme weather events, cause expanded desertification in the tropics, shift plant and animal populations, and eventually change the optics of the atmosphere and surface, all to restore some measure of balance.

We must accept that climate is a nonlinear adaptive system in dynamic equilibrium, with any number of quasi-stable preferred states (attractors), only one of which we can observe right now. Those of you who have read some of Ed Lorenz's early work in climate and atmospheric science, or the superb Chaos by James Gleick, will know what I mean here. We can then be reasonably sure that positive and negative feedbacks built into the climate system will become more and more evident in their effects on restoration of balance, and we'll see some of this evidence as the process moves along. If things get really out of balance, then we might reach a tipping point, beyond which the system will settle into another quasi-stable state as our next climate pattern. Since we don’t really know what that state will look like, let's just hope that humans can live with it.

And finally, in the last point I made above, I will certainly admit to a criticism of the long-standing environmental movement. We cannot "save the Earth" because we are but dust on the surface, and the Earth will still be here long after humans have passed from sentience, unless we get hit by a very large comet, I suppose. Toxic waste, polluted water, polluted air, nuclear winter, felled forests, dammed rivers, species extinction, greenhouse gases--all of these suggest only that we as humans are getting better at causing injury to ourselves, but the Earth recovers and re-establishes balance in its own way. We can "save the whales" and "ban the nukes" and do all that we can to preserve out own lives, but the planet and its oceans and atmosphere will still do what they can to keep things in balance. If we can't deal with it, we'll go the way of the dinosaurs. Rapid regime shifts and extreme events are some of the many ways that we will recognize these impulse-response couplings in the Earth science system, and we must remain ready, willing, and funded to study these couplings and events and shifts in order to increase our species' resilience and sustainability. Save the humans!

So, on the topic of extremes, here was the list of weather events in recent months that the UN report attributed to global warming:
  1. Twice as many Indian monsoon depressions as normal in the season's first half, leading to catastrophic flooding across South Asia, 500 deaths, the displacement of 10 million people, and the destruction of vast areas of farmland and property.
  2. The first documented cyclone in the Arabian Sea, Cyclone Gonu hit Oman and Iran in early June, killing 50 and affecting 20,000 others.
  3. Heavy rains in China over 6-10 June affected 13.5 million citizens, killing 120 in flooding and landslides.
  4. The wettest May-to-July period for England and Wales ever recorded in more than two centuries of weather record keeping. Intense one-day bursts in June and July caused extensive flooding, killed nine and caused an estimated $6 billion in damages.
  5. Germany recorded its driest April on record, and then saw nearly twice the normal rain for May since record keeping began more than a century ago.
  6. Torrential rains and ferocious winds across Europe in January, leading to the death of 47 and electricity outages affecting thousands.
  7. February floods in Mozambique, the worst in six years, killed 30 and led to the evacuations of 120,000.
  8. Overflowing of the Nile River from heavy and early rainfall in Sudan since the end of June, and the flooding has damaged thousands of homes.
  9. 68 islands and 16 atolls in the Maldives were swamped in May by huge wave swells, up to 14 feet in height.
  10. Uruguay had its worst floods since 1959 in May, affecting 110,000 people and severely damaging crops and buildings.
  11. Southern Europe was affected by two heat waves in June and July, breaking a series of temperature records and spawning dozens of wildfires. Bulgaria recorded a new high temperature of 113 degrees, and other areas experienced temperatures exceeding 104 degrees.
  12. A heat wave during May in western and central Russia broke temperature records, including a 91 degree mark in Moscow that broke a 116-year-old record.
  13. April ranked in many countries across Europe as the warmest ever recorded.

I subscribe to the assessment put forth in the Washington Post article of 4 August 2006: "...it is impossible to attribute any one weather event to climate change..." This is also called doubt, though not to the degree that the AAPG still doubts the sum of scientific evidence for global warming that is already established. My doubt, and maybe that of the article's author, is based on the views that planetary climate is large-scale in both space and time, and that climate changes over time can be best evaluated statistically, without necessarily picking out one or two specific events. The list provided by the UN report is actually a mix of individual or isolated weather events (nos. 2, 3, 4, 6, 12), climate analyses (nos. 1, 5, 11, 13), hydrologic events with no listed attribution (nos. 7, 8, 10), and oceanography (no. 9). Of the climate-related events listed, two are temperature-related, and one of these (no. 11) might be attributed to transient nonlinear feedback in the synoptic weather over Europe, specifically the formation of blocking patterns. Another (no. 13) is simply a restatement of the premise, that warming results in warm weather.

That leaves two recent events (nos. 1 and 5) that we must examine physically in order to demonstrate the impacts, if any, of global warming in the climate system. It is easy enough to suggest that both of these events are signs of an intensified hydrologic cycle, given the extraordinary rainfall totals and flooding that resulted. But what is that "intensification," physically? Basically, the atmosphere is attempting to move energy poleward more quickly, because of greater lateral gradients in temperature. The process experiences greater instability, and breakdown of the synoptic patterns result more frequently, because the development of meridional flows move warm air (the excess energy) poleward more quickly than a quiescent or zonal flow regime. Remember, global warming is supposed to slow the ocean circulations, so the atmosphere must make up for the poleward transport of heat energy that the oceans, which have a much greater heat capacity, no longer provide. The results: more monsoon depressions over the tropical Indian Ocean, which then propagate onto the subcontinent and drop their massive moisture content, and more middle-troposphere lows and fronts over the mid-latitude Atlantic Ocean, which then move with the prevailing flow onto the European continent.

Some of the other weather events may have similar causes and origins, but it is the consistency of these two "events" that is most indicative of steadily intensified forcing from warming patterns at the surface and in the atmosphere. That's the most apparent, and least statistical, sign of "global" warming, and the changes in climate have come so slowly and consistently that we've finally noticed, because we're still just beginning to understand the physical mechanisms of these processes.

3 comments:

snowbird said...

Global Warming?

Dear Editor,

Recent research by Henrik Svensmark and his group at the Danish National
Space Center points to the real cause of the recent warming trend. In a
series of experiments on the formation of clouds, these scientists have
shown that fluctuations in the Sun's output cause the observed changes in the
Earth's temperature.

In the past, scientists believed the fluctuations in the Sun's output were
too small to cause the observed amount of temperature change, hence the need
to look for other causes like carbon dioxide. However, these new
experiments show that fluctuations in the Sun's output are in fact large
enough, so there is no longer a need to resort to carbon dioxide as the
cause of the recent warming trend.

The discovery of the real cause of the recent increase in the Earth's
temperature is indeed a convenient truth. It means humans are not to blame
for the increase. It also means there is absolutely nothing we can, much
less do, to correct the situation.

Thomas Laprade
480 Rupert St.
Thunder Bay, Ont.
Canada
Ph. 807 3457258



http://discovermagazine.com/2007/jul/the-discover-interview-henrik-svensmark

http://environment.newscientist.com/article.ns?id=dn11462

http://mypetjawa.mu.nu/archives/188993.php

M. Garcia said...

There has certainly been some question over the solar cycle and its possible role in global warming observations. A Science article in 1999 by researchers at the NASA Goddard Institute for Space Studies (see press release) concluded that the impact of solar variability was secondary to the build-up of greenhouse gases. More recently, an article carried by the BBC on 10 July 2007 was titled "'No Sun link' to climate change" and reported on an international analysis of solar observations that were recently published by the Royal Society, so I think that speaks for itself

The first sentence in that Discover article states that "most leading climate experts don’t agree with Henrik Svensmark, the 49-year-old director of the Center for Sun-Climate Research at the Danish National Space Center in Copenhagen." I suggest to you that the consensus and conclusions reached on the causes of global warming have been neither easy nor convenient, and I would guess that lots of ideas were entertained before scientists finally pointed fingers back at ourselves. Some on the edges of the debate still think that the environmentalists have not proven their point, and I disagree. I still, however, think that a lot of people need to continue looking at the problem and, yes, its possible solutions, at least for the sustainability of our own species.

BHUVAN CHAND said...

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