More repercussions of a warming planet

pattylou

From last week's Science Daily headlines:

Underlying Cause Of Massive Pinyon Pine Die-off Revealed

The resulting landscape change will affect the ecosystem for decades. Hotter temperatures coupled with drought are the type of event predicted by global climate change models. The new finding suggests big, fast changes in ecosystems may result from global climate change.

"We documented a massive forest die-off – and it's a concern because it's the type of thing we can expect more of with global warming," said research team leader David D. Breshears, a professor of natural resources in The University of Arizona's School of Natural Resources in Tucson and a member of UA's Institute for the Study of Planet Earth.

http://www.sciencedaily.com/releases...1011073510.htm

The article says nothing about man's contribution to warming; it is merely another datapoint of the changing face of the planet.

Andre

However, the summary for policy makers is mainly concerned about increasing precipitation:

It is very likely7 that precipitation has increased by 0.5 to 1% per decade in the 20th century over most mid- and high latitudes of the Northern Hemisphere continents, and it is likely7 that rainfall has increased by 0.2 to 0.3% per decade over the tropical (10°N to 10°S) land areas. Increases in the tropics are not evident over the past few decades. It is also likely7 that rainfall has decreased over much of the Northern Hemisphere sub-tropical (10°N to 30°N) land areas during the 20th century by about 0.3% per decade. In contrast to the Northern Hemisphere, no comparable systematic changes have been detected in broad latitudinal averages over the Southern Hemisphere. There are insufficient data to establish trends in precipitation over the oceans.

In the mid- and high latitudes of the Northern Hemisphere over the latter half of the 20th century, it is likely7 that there has been a 2 to 4% increase in the frequency of heavy precipitation events. Increases in heavy precipitation events can arise from a number of causes, e.g., changes in atmospheric moisture, thunderstorm activity and large-scale storm activity

Obviously if global warming is about water vapor feedback, the atmospheric contents of water vapor should also be increasing, causing more precipitation.

Perhaps indeed we see a problem here, accounting aridness to global warming. Incidentely, if you have Google earth installed, why not fly over the Sahara and see the incredible density of empty river beds, not caused by anthropogenic global warming.

pattylou

(I assume the river beds had millennia (times millennia) to dry out... so I don't know that such a google-earth would be informative of anything relevant to the present question!)

My understanding of the models include more extreme weather across the board. More "climate dysjunction" as I linked a few weeks ago. More severe rains, more droughts, more heat waves, and so on.

I am glad to see from your source that we will not become a desert planet (not that I thought we would). Your information is also consistent with models --- climate change is predicting changes in weather patterns.

thanks Andre, always a pleasure.

pattylou

Coincidentally this headline ran the same day as the pinyon pine story. It describes how precipitation intensity (the strength of a downpour) and drought could both increase in the same area.

Warmer Seas, Wetter Air Make Harder Rains

<snip>Though water vapor increases the most in the tropics, it also plays a role in the midlatitudes, according to the study. Combined with changes in sea-level pressure and winds, the extra moisture produces heavier rain or snow in areas where moist air converges.

In the Mediterranean and the U.S. Southwest, even though intensity increases, average precipitation decreases. The authors attribute the decrease to longer periods of dry days between wet ones. The heavier rain and snow will most likely fall in late autumn, winter, and early spring, while warmer months may still bring a greater risk of drought.

http://www.sciencedaily.com/releases...1014072404.htm

Again, nothing in this article concrete about man's contributions, though greenhouse gasses are said to be increasing in the article, which hints that the authors lie within the consensus opinion. The *science* in the article is looking simply at how a warming planet affects the extremes of weather. Heavier rains, more droughts, etc.

Andre

Incidentely noticing the pertinent language (will this, will that) your article is an excellent example of the promotion of models from producing predictions to verify the validity of a hypothesis to a prediction of the future.

or from Crighton:

To an outsider, the most significant innovation in the global warming controversy is the overt reliance that is being placed on models. Back in the days of nuclear winter, computer models were invoked to add weight to a conclusion: "These results are derived with the help of a computer model." But now large-scale computer models are seen as generating data in themselves. No longer are models judged by how well they reproduce data from the real world-increasingly, models provide the data. As if they were themselves a reality. And indeed they are, when we are projecting forward. There can be no observational data about the year 2100. There are only model runs.

This fascination with computer models is something I understand very well. Richard Feynmann called it a disease. I fear he is right. Because only if you spend a lot of time looking at a computer screen can you arrive at the complex point where the global warming debate now stands.

Nobody believes a weather prediction twelve hours ahead. Now we're asked to believe a prediction that goes out 100 years into the future? And make financial investments based on that prediction? Has everybody lost their minds?

Stepping back, I have to say the arrogance of the modelmakers is breathtaking. There have been, in every century, scientists who say they know it all. Since climate may be a chaotic system-no one is sure-these predictions are inherently doubtful, to be polite. But more to the point, even if the models get the science spot-on, they can never get the sociology. To predict anything about the world a hundred years from now is simply absurd.

Moreover it does not make sense. Strong weather hinges on two factors, high surface temperatures and more importantly high temperature gradients in the lower atmosphere causing the atmosphere to be unstable. The way greenhouse gas is supposed to work, the atmosphere warming up due to IR absorption hence the gradients will decrease, making the atmosphere more stable. Hence it's not logical at all that greenhouse gas warming causes more extreme weather.

Andre

Oh and the Sahara turned from moist to arid and back several times some 4000 years ago.

Andre

Furtermore, I wonder why these kind of hell and disaster shouting publications, which are actually only discussing (GIGO) models, get all the attention; whilst conveniently overlooking reality check publications like these

Overall, I find that the observed Northern Hemisphere circulation trend is inconsistent both with simulated internal variability and with the simulated response to human and natural climate influences, although the mean simulated zonal index trend is consistent in sign with that observed. This is therefore an important aspect of large-scale climate change that these state-of-the-art climate models are unable to simulate; if we could understand and correct this bias, predictions of future regional climate change would be improved.

pattylou

Intriguing stuff.

My position is certainly not "The models are right" and again, I know of no scientists with that mindset. (models serve many functions but are certainly not something to be adhered to blindly, particularly climate change models!) Crichton earns his pay by writing science-based disaster scenario fiction. He has a unique perspective but is given to extremity in his writing.

My position is more along the lines of "Our best scientific understanding is that GHG emissions are contributing to climate change. We see dramatic change in climate already (not modelled, but real and present) so let's try to curb emissions, as we recognize those are a likely significant contributing factor. Curbing emissions may or may not solve the problem completely, but based on our current understanding it could help the situation."

Andre

Dear Patty,

How sure are we that "dramatic change in climate already" are really unnatural? We say dramatic climate changes thoughout the Pleistocene and Holocene. Is there really something new?

if you'd have the time to study the comprehensive overview of Spencer Weart, you will see that are two main incentives for global warming, a little bit of Arrhenius' inaccurate GHG effect calculations but mostly the perception of the ice ages, assuming that big warming and GHG concentrations are perfectly synchronised.

That second factor however is completely out of control. Not everybody has taken the time to read and combine a few hundred ice ages papers and abstracts very critically, knowing what the main problems are: misinterpretation of isotope ratio changes and the failure to correct old carbon datings with the modern calibration tables (like INTCAL04 Reimer et al 2004). Abbarations accumulate to over 4500 years or some 25% which makes apparantly codating events to be in fact thousands of years apart - but nobody is interested anymore.

After having done that, remaining is a perfectly clear mechanism that answers most of the questions like the Mammoth extinction for instance but it also makes clear that we are seeing totally different -noneless physically sound and quantifiable- things in the cores. This falsifies the alleged correlation between CO2 and temperature. Of course there have been major temperature changes but not synchronized with the isotopes.

If science would have know about those mentioned factors 20 years ago, then there would not have been a global warming hype at all, because it would not have made sense whatsoever.

pattylou

How sure are we that "dramatic change in climate already" are really unnatural? We say dramatic climate changes thoughout the Pleistocene and Holocene. Is there really something new?

I have never said that we know that present warming is "unnatural." Rather, I have said that we know that the planet is warming. It's warming dramatically (from a climate standpoint; this is not to be seen as a doomsday statement), and it's warming hand-in-hand with humans coming to dominate the planet. We are past the "natural" carrying capacity of the planet, and are needing to deforest and burn fossil fuels (etc, genetic engineering of crops, diversion of waterways, etc etc) in order to feed the population load of humans on the planet.

To the extent that we have changed the planet to sustain our own lives (converting large tracts of diverse biological systems such as forests to single-plant-species environments like cornfields, and using "artificial" methods such as burning petroleum products to accomplish large scale farming), and remembering that systems on the planet are interconnected, it seems likely to me that you simply cannot remove humans from the equation of how climate is changing.

I've never personally put a percentage on how much of climate change can be attributed to people's activity, but it is obvious that we are a part of the system. Since we are fortunate enough to have intelligence and foresight, it seems reasonable to "make our best guess" to avoid further disruption of non-human natural systems on the planet (ecosystems, etc.) This best guess, in my opinion, includes reduction of fossil fuel consumption.

Thank you for the link. I'll visit it.

Andre

It's warming dramatically

Why? Is 0,6 degrees C in more than a century dramatical or the current trend of some 0,15 degrees per decade? Oh yes we had a few good summers. But according to the ice core specialists Earth endured temperature changes of about 10 degrees per decade at the end of the Pleistocene. They are wrong and I can explain why, but several spikes of the Moberg 2000 years reconstruction are certainly matching the current temperature changes. Moreover despite the shouting headlines, the lower troposphere is still unwilling to concur with those fast temperature changes.

it's warming hand-in-hand with humans coming to dominate the planet

My early investigations brought me to Plato's Atlantis very quickly. Why? The Mammoths went extinct at the end of the Younger Dryas, some 11,600 Before Present ("Present" being 1950) and Atlantis was supposed to be destroyed 9000 years before Solon's trip to Egypt. Which is 1950+530+9000=11,480 years BP. Is the stunning accuracy of about 1% enough to assume that the destruction of Atlantis and the extinction of the Mammoth had the same cause..?

Perhaps you understand that I was fully convinced of that idea for several months until somebody else explained/proved that Atlantis is really a myth indeed in a most brilliant way. It thaught me about the "affirming the consequence"-fallacy the hard way. Coincidence can never be ruled out.

Since we are fortunate enough to have intelligence and foresight, it seems reasonable to "make our best guess" to avoid further disruption of non-human natural systems on the planet (ecosystems, etc.) This best guess, in my opinion, includes reduction of fossil fuel consumption.

A definite maybe. Use of fossil fuels should be terminated (eventually) to transit to a sustainable/renewable energy source but it does not have much (if any) impact on climate. The essential difference is where to put priorities. I don't know the schedule to accomplish a sustainable energy management but I'm sure that there is considerable priority for a lot of environmental issues to solve directly, disregarding futile CO2 and climate issues

*X-43D*

Global warming is a serious problem and many developing countries are facing droughts because of it. Droughts lead to desertification and starvation.

http://news.bbc.co.uk/1/hi/world/africa/4587584.stm

russ_watters

Ethiopia is a bad example. It is "chronically food insecure" meaning even the slightest reduction in food output due to normal year-to-year fluctuations causes a famine. Ie, the 1984 famine.

http://www.worldpress.org/Africa/948.cfm

So far, there have not been any climate issues that can really be pinned on global warming.

*X-43D*

Lack of foreign investment in infrastructure and technology (electricity, cars and distillation facilities) makes things much worse.

Mk

Oh yes, blame it on the US and Europe. Everything is their fault.

Quote by Andre

Oh and the Sahara turned from moist to arid and back several times some 4000 years ago.

I would like to see a reference for that so as to expand my knowledge.

Thanks you,
Mk

*X-43D*

Droughts are caused mainly due to natural conditions rather than political ones. Thus global dimming, contamination, distruction of forests and lack of infrastructure and technology all worsen the situation.

Andre

Quote by Mk

I would like to see a reference for that so as to expand my knowledge

Well since you ask so politely

This one mentions the 4000 years:

http://www-bprc.mps.ohio-state.edu/Icecore/589.pdf

the basic standard work on the African Humid Period makes it end a little earlier (5,5 Kya) is:

deMenocal, P. et al., 2000. Abrupt onset and termination of the African Humid Period: rapid climate responses to gradual insolation forcing. Quat. Sci. Rev. 19, 347-361.

But I can't find a easy link right now. If you want a copy PM your E-mail address.

also:

http://www.ldeo.columbia.edu/~peter/...ience.2000.pdf

http://www.pik-potsdam.de/~claussen/...ot_igbp_02.pdf

The African Humid Period ties in extremely well with the Non calor sed umor hypothesis.

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Andre Blog Entries: 2 Recognitions: Gold Member	Oh and the Sahara turned from moist to arid and back several times some 4000 years ago.

X-43D	Global warming is a serious problem and many developing countries are facing droughts because of it. Droughts lead to desertification and starvation. http://news.bbc.co.uk/1/hi/world/africa/4587584.stm

russ_watters Mentor	Ethiopia is a bad example. It is "chronically food insecure" meaning even the slightest reduction in food output due to normal year-to-year fluctuations causes a famine. Ie, the 1984 famine. http://www.worldpress.org/Africa/948.cfm So far, there have not been any climate issues that can really be pinned on global warming.