Re: INFOTERRA: News: Minor Shifts In Temperature Have Major Habitat Effects
Dear Infoterrans,
Thanks to Ashwani who forwarded the messages, we now have an idea how
global temperature changes affect species. A global rise in temperature
gives a shift toward the poles of app. 6 km per decade, or 61 km in the
last century. This seems not to be that much (except if the shift goes on,
even decades after a stabilised temperature trend). From history, it is
known that grapes could be grown up to the Nordic countries, but anyway in
large quantities in our country, during the Medieval Warm Period (around
900-1200 AD). That completely was destroyed during the Little Ice Age. And
until recently, the border for grapes growing in open fields was some 350
km more to the South (except for shielded valleys like Mosel and Rhine).
That should implicate that the temperatures during the Medieval Warm Period
were some 6 degr.C higher than now, which is rather unlikely. But a one
degr.C higher temperature in that period was probably true, and entirely
natural.
Thatalso implies that most species will survive (and have survived) far
more rapid changes in global temperature than we see now (natural or not),
as was already known from very rapid changes (10 degr. C in less than a few
decades) in certain periods the earth has encountered.
What should be interesting is to see how nature reacts on natural
oscillations with a very high and fast impact on temperatures and
drought/floods, as what results from the NOA and ENSO events. From that we
can learn how nature may adapt to global changes...
Sincerely,
Ferdinand Engelbeen
------------------------------
At 20:50 1/2/03 -0800, Ashwani Vasishth forwarded:
>http://www.latimes.com/news/science/la-sci-species2jan02,0,6033999.story?coll=la%2Dnews%2Dscience
>
>Los Angeles Times:
> January 2, 2003
>
>THE NATION
>Minute Shift in Temperature Has Had a Major Effect on Earth, Studies Show
> Species are migrating northward because of 1-degree increase in last
>100 years, data reveal. It also has sped up spring flowering, egg
>hatching.
>
>By Usha Lee McFarling, Times Staff Writer
>
>Gradual warming over the last 100 years has forced a global movement of
>animals and plants northward, and it has sped up such perennial spring
>activities as flowering and egg hatching across the globe -- two signals
>that the Earth and its denizens are dramatically responding to a minute
>shift in temperature, according to two studies published today.
>
>One study showed that animals have shifted north an average of nearly four
>miles per decade. Another study showed that animals are migrating,
>hatching eggs and bearing young an average of five days earlier than they
>did at the start of the 20th century, when the average global temperature
>was 1 degree cooler.
>
>That 1 degree, according to the studies, has left "climatic fingerprints"
>-- pushing dozens of butterfly and songbird species into new territories,
>prompting birds and frogs to lay eggs earlier and causing tree lines to
>march up mountain slopes.
>
>In some cases, the shifts have been dramatic. The common murre, an Arctic
>seabird, breeds 24 days earlier than it did decades ago. And some
>checker-spot butterflies shifted their range northward by nearly 60 miles
>in the last century.
>
>Although many individual shifts in timing and range have been reported by
>field biologists, the studies published in today's issue of Nature are the
>first to establish that a variety of organisms in myriad habitats are
>responding in similar ways to climatic change.
>
>"There is a consistent signal," said Terry L. Root, a biologist at
>Stanford University and lead author of one report. "Animals and plants are
>being strongly affected by the warming of the globe."
>
>Root said she was surprised that the two Nature studies were able to
>detect the effect. She said she thought the increased temperature was too
>small to cause widespread change. Root also said she expected that any
>damaging effects of climatic change would be unnoticeable amid the
>enormous habitat destruction in modern times caused by development,
>pollution and other human activities.
>
>"It was really quite a shock, given such a small temperature change," she
>said.
>
>Many scientists have debated whether plants and wildlife have been widely
>affected by climatic change. Some have argued that no widespread response
>has occurred and that a few examples of animals changing the timing of
>their migration or reproduction have been used by environmental groups to
>overstate the dangers of global warming.
>
>The new studies attempt to override such criticism by analyzing thousands
>of reports of biological change and correlating them with climatic change.
>"People said there wasn't a quantitative analysis and it was just
>storytelling," said University of Texas biologist Camille Parmesan, who
>led the other Nature study. "This is the first hard-core, quantitative
>analysis."
>
>The changes are not necessarily bad for all species. The earlier hatching
>of eggs gives some bird species a chance to lay two clutches of eggs per
>summer instead of one, Root said. With less frost in late spring and early
>fall, the growing season of many plants has been extended; crop yields are
>also up.
>
>But the scientists are concerned that warming will harm some species,
>particularly those already at risk. The extinction of the golden toad from
>the cloud forests of Costa Rica has been linked by some scientists to heat
>stress, Root said. And chicks of the jewel-colored quetzal bird in the
>same forest are now being preyed upon by toucans that moved to higher
>elevations in the forest as temperatures warmed, she said.
>
>Ecosystems could also be at risk, she added, if insects mature too late to
>pollinate plants that now flower earlier. The earlier migration of wood
>warblers is leaving behind spruce trees full of spruce budworm
>caterpillars, which devastate the trees and leave the timber damaged.
>
>"If we've had so much change with just one degree, think of how much we
>will have with 10 degrees," Root said, referring to projections by the
>Intergovernmental Panel on Climate Change on how high temperatures could
>rise in the next 100 years. "In my opinion, we're sitting at the edge of a
>mass extinction."
>
>But such worst-case scenarios underestimate the ability of biological
>entities to adapt, some experts say. In a report written for the George C.
>Marshall Institute, Lenny Bernstein, an expert on the social and economic
>effect of climatic change, said some "marginal species" will become
>extinct. He added, however, that plants and animals have always faced
>climatic changes and that they often have survived. Future human
>intervention could help increase survival rates, he said.
>
>Although the new studies do not address the cause of the recent warming,
>most scientists agree it is due to a mix of human and natural factors. An
>increasing number of scientists say that the warming is occurring at a
>rate unprecedented in the recent geological past and that it will be
>peppered by more extreme events, including heat waves, droughts, storms
>and floods.
>
>"It's not just the gradual warming that impacts individuals, it's these
>extreme events," Parmesan said.
>
>Convinced that wild animals and plants will need more room if warming
>continues, Root and Parmesan advocate including climatic change
>projections into long-range planning for wildlife management. Preserves
>may offer more options for survival if they run in a north-south
>direction, contain elevation gains or are connected to neighboring
>reserves, the scientists said.
>
>"Since we can't count on climate being stable," Parmesan said, "you need
>to give the organisms a chance to go through some unstable periods."
>
>Copyright 2003 Los Angeles Times
>
>*** NOTICE: In accordance with Title 17 U.S.C. Section 107, this material
>is distributed, without profit, for research and educational purposes
>only. ***
>
>
> * * *
>
>http://news.bbc.co.uk/2/hi/science/nature/2617139.stm
>
>Wednesday, 1 January, 2003, 22:36 GMT
>
>Wildlife Seeks Cooler Climes
> Species are on the move, say scientists
>
>By Alex Kirby
>BBC News Online environment correspondent
>
>Two groups of US biologists say they have detected a consistent pattern of
>response by wild species to warmer temperatures.
>
>They say this is evidence that climate change is affecting living systems,
>as climatologists have predicted.
>
>Many species are forsaking their ranges to find cooler or higher habitats.
>
>And several regular springtime events are now happening earlier than they
>did a few decades ago.
>
>The biologists' work is reported in the journal Nature.
>
>Camille Parmesan, of the University of Texas at Austin, and colleagues
>conducted a "meta-analysis" of studies of more than 1,700 species.
>
> The balance of evidence from these studies strongly suggests that a
>significant impact of global warming is already discernible in animal and
>plant populations
>
>They say there have been "significant" moves in range averaging 6.1 km
>(3.8 miles) per decade towards the poles, or metres per decade upwards.
>
>Spring events, such as the arrival of migrant species and the laying of
>eggs, have advanced by 2.3 days per decade.
>
>Unconvinced
>
>The authors note the difficulties experienced by the Intergovernmental
>Panel on Climate Change (IPCC) in assessing how far recent observed
>changes in natural biological systems have been attributable to climate
>change.
>
>They write: "Differences of opinion among disciplines can stem naturally
>from whether the principal motivation is to assess the magnitude of
>immediate impacts or of long-term trajectories.
>
>"Most field biologists are convinced that they are already seeing
>important biological impacts of climate change. However, they have
>encountered difficulty in convincing other academic disciplines,
>policy-makers and the general public."
>
>The picture that emerges from their study, they argue, is persuasive in
>the round, even though individual species may not show a marked response
>to warming temperatures.
>
>They write: "The test for a globally coherent climate fingerprint does not
>require that any single species show a climate change impact with 100%
>certitude.
>
>"Rather, it seeks some defined level of confidence in a climate change
>signal on a global scale."
>
>In the second study Terry Root of Stanford University, California, and
>colleagues also report a temperature-related fingerprint in the behaviour
>of a range of species.
>
>They found the changes were most marked at high latitudes and high
>altitudes, where the largest temperature changes are predicted.
>
>Their meta-analysis included information on species and global warming
>from 143 separate studies.
>
>'Significant impact'
>
>The authors say: "These analyses reveal a consistent temperature-related
>shift, or 'fingerprint', in species ranging from molluscs to mammals and
>from grasses to trees...the balance of evidence from these studies
>strongly suggests that a significant impact of global warming is already
>discernible in animal and plant populations.
>
>"The synergism of rapid temperature rise and other stresses, in particular
>habitat destruction, could easily disrupt the connectedness among species
>and lead to a reformulation of species communities...and to numerous
>extirpations and possibly extinctions."
>
>Because they were looking for trends, the authors say, they excluded
>studies examining climatic cycles such as the North Atlantic Oscillation
>and the El Nino cycle in the Pacific west of Chile.
>
>Some scientists continue to maintain that climate change, if it is
>happening, is an entirely natural phenomenon which cannot be explained in
>terms of human behaviour.
>
>The two Nature studies may not be able to advance discussion of that
>argument.
>
>But they do suggest that wildlife is aware of and responding to a new
>reality, whatever its causes.
>
>*** NOTICE: In accordance with Title 17 U.S.C. Section 107, this material
>is distributed, without profit, for research and educational purposes
>only. ***
-------------------------------
Ferdinand Engelbeen
Oude Ertbrandstraat 12
B-2940 Stabroek
Belgium
Tel. +32-3-605.38.14
Fax +32-3-605.43.96
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