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Seven Climate Models, Seven Different Answers

landsat Oman
© unknown

In a new report, scientists used seven different climate models to assess human induced land cover change (LCC) at regional and global scales. The first results from the LUCID (Land-Use and Climate, IDentification of robust impacts) intercomparison study by Pitman et al. show no agreement among the models. This study indicates that land cover change is "regionally significant, but it is not feasible to impose a common LCC across multiple models for the next IPCC assessment." In other words, this important factor is missing from current models and scientists are at a loss as to how to add it.

The study, soon to be published in Geophysical Research Letters, performed the type of analysis that was recommended in the 2005 National Research Council report on how to improve climate model accuracy. The results were both as expected, LCC proved to be an important missing factor, and unexpected in that none of the seven models tested yielded the same results. This throws modelers into a quandary regarding how to proceed. Here is the abstract of the paper by A. J. Pitman et al.:
"Seven climate models were used to explore the biogeophysical impacts of human induced land cover change (LCC) at regional and global scales. The imposed LCC led to statistically significant decreases in the northern hemisphere summer latent heat flux in three models, and increases in three models. Five models simulated statistically significant cooling in summer in near-surface temperature over regions of LCC and one simulated warming. There were few significant changes in precipitation. Our results show no common remote impacts of LCC. The lack of consistency among the seven models was due to: 1) the implementation of LCC despite agreed maps of agricultural land, 2) the representation of crop phenology, 3) the parameterisation of albedo, and 4) the representation of evapotranspiration for different land cover types. This study highlights a dilemma: LCC is regionally significant, but it is not feasible to impose a common LCC across multiple models for the next IPCC assessment."

Bell

Change In Ice Ages Not Caused By CO2

ice age
© unknown

Around 1.2 million years ago, a shift in global climate began that caused a change in the timing of the alternating warm and cold periods - called interglacials and glacials - that have persisted during the Pleistocene Ice Age. Prior to that time, ice age glacial periods lasted about 40,000 years but since ~700,000 years ago ice-age cycles have lasted for around 100,000 years. Orbital variations, called the Croll-Milankovitch cycles, do exert some forcing on the 100,000 year time scale, but it is relatively weak. Orbital cycles seem to many too feeble an explanation for the change in glacial-interglacial timing. Some scientists have attempted to attribute the timing shift to a drop in CO2 but a new study confirms that carbon dioxide levels were not the cause of the climate shift.

The dominant period of Pleistocene glacial cycles changed during the mid-Pleistocene from 40,000 years to 100,000 years, for reasons unknown to science. A new paper in the June 19, 2009, edition of Science investigates whether that shift could be attributed to changes in atmospheric CO2 levels. A group of researchers, led by Bärbel Hönisch, examined the factors that influenced the mid-Pleistocene transition (MPT) around 1250 to 700 thousand years ago. Here is the published abstract of the paper:
The dominant period of Pleistocene glacial cycles changed during the mid-Pleistocene from 40,000 years to 100,000 years, for as yet unknown reasons. Here we present a 2.1-million-year record of sea surface partial pressure of CO2 (PCO2), based on boron isotopes in planktic foraminifer shells, which suggests that the atmospheric partial pressure of CO2 (pCO2) was relatively stable before the mid-Pleistocene climate transition. Glacial PCO2 was ~31 microatmospheres higher before the transition (more than 1 million years ago), but interglacial PCO2 was similar to that of late Pleistocene interglacial cycles (<450,000 years ago). These estimates are consistent with a close linkage between atmospheric CO2 concentration and global climate, but the lack of a gradual decrease in interglacial PCO2 does not support the suggestion that a long-term drawdown of atmospheric CO2 was the main cause of the climate transition.

Extinguisher

Oil Boom Threatens The Last Orang-utans

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© Kathy MarksRazed lowland forest on Sumatra island awaits a palm oil plantation
A famous British company, Jardines, is profiting as the lowland forest - which shelters the few remaining orang-utans - is razed to make way for massive palm oil plantations, reports Kathy Marks in Tripa, Indonesia

Bizarro Earth

Andres weakens to tropical storm

Andres
© Associated Press/NOAAThis satellite image released by NOAA shows Andres, center, in the Pacific Ocean on Tuesday June 23, 2009. Andres has been downgraded from hurricane to tropical storm and could drop 6 inches of rain on Mexico
Forecasters say Tropical Storm Andres has weakened from a hurricane off the southwestern coast of Mexico and that it could dump 3 to 6 inches of rain on parts of the country.

The National Hurricane Center says the storm's maximum winds have decreased to 70 mph from near 75 mph earlier Tuesday.

Andres is forecast to weaken even more in the next day.

The center of the storm as of 11 p.m. EDT was about 110 miles (180 kilometers) west-southwest of Manzanillo.

Andres is moving near 10 mph (17 kph) toward the northwest. It is forecast to track toward the west-northwest and pass very close to or over the southwestern coast of Mexico.

Evil Rays

Australian Climate Change Minister Penny Wong doesn't have the answers

Steve Fielding recently attended a climate change conference in Washington, DC. Listening to the papers presented, the Family First senator became puzzled that the scientific analyses they provided directly contradicted the reasons the Australian government had been giving as the justification for its emissions trading legislation.

Fielding heard leading atmospheric physicist Dick Lindzen, of the Massachusetts Institute of Technology, describe evidence that the warming effect of carbon dioxide was much overestimated by computer climate models and remark: "What we see, then, is that the very foundation of the issue of global warming is wrong.

"In a normal field, these results would pretty much wrap things up, but global warming-climate change has developed so much momentum that it has a life of its own quite removed from science."

Another scientist, astrophysicist Willie Soon, from the Harvard-Smithsonian Centre for Astrophysics, commented: "A magical CO2 knob for controlling weather and climate simply does not exist." Think about that for a moment with respect to our government's climate policy.

On his return to Canberra Fielding asked Climate Change Minister Penny Wong to answer three simple questions about the relationship between human carbon dioxide emissions and alleged dangerous global warming.

Fielding was seeking evidence, as opposed to unvalidated computer model projections, that human carbon dioxide emissions are driving dangerous global warming, to help him, and the public, assess whether cutting emissions would be a cost-effective environmental measure.

After all, the cost to Australian taxpayers of the planned emissions trading bill is about $4000 a family a year for a carbon dioxide tax of $30 a tonne. The estimated benefit of such a large tax increase is that it may perhaps prevent an unmeasurable one-ten-thousandth of a degree of global warming from occurring. Next year? No, by 2100.

Igloo

US Global Warming: New York senators want disaster declaration for May freeze

Grape harvests hampered by unseasonably low temperatures have become a concern not only for area farmers, but United States Senators who are now calling for an emergency response from state officials.

Following a late seasonal frost in May, area grape growers suffered overall crop losses in the neighborhood of 15-20 percent - or upwards of $3-4 million in Chautauqua County alone, which farms around 17,000-20,000 acres - according to Jay Hardenburg, regional manager of member relations for National Grape Cooperative Inc., at the time. In the face of such devastating crop losses, area grape growers were left with doubts about future harvests in addition to the dead fruit hanging on their vines this year.

"The damage from the frost ... was fairly extensive, not just in Chautauqua County, but throughout the Lake Erie Grape Belt, stretching all the way from Hamburg-North Collins area to all the way out west towards Cleveland, Ohio," Hardenburg said in May.

On Wednesday, however, U.S. Senators Charles E. Schumer and Kirsten Gillibrand - the first New York Senator in nearly 40 years to serve on the Senate Agriculture Committe - urged New York state officials to request a disaster declaration for areas of Chautauqua, Cattaraugus and Erie counties in order to provide urgently needed disaster assistance to the many farmers affected.

Binoculars

Iowa, US: Harsh winter leaves mark on flowers, trees, crops

The thermometer says another Iowa summer has arrived. But winter continues to hang around in the form of dead trees, flowers, plants and shrubs that were unable to rebound from one the snowiest and coldest seasons on record.

The state's summer palette might be a bit heavy on brown as a result.

"We've had some real damage here," Bob Atha of Appleberry Farm in Marshalltown said. "I don't know about other places, but we're expecting about half the apples we had last year, maybe a little less than half."

Experts call it "winterkill," and it's been reported from the alfalfa fields of Ontario to the wheat stands of Kansas to golf courses in Massachusetts.

In Iowa, the bitter cold and early snow was hard on even the hardiest evergreens. An early spring didn't help, either.

"We've had literally hundreds of people calling and complaining about" winter-ravaged bushes and shrubs, said Jeff Westphal, a salesman at Miller Nursery in Johnston. "Some of them were already weak going into the winter. But that doesn't explain what happened to the boxwoods and yews. I think it was just too cold for some of them."

Bell

Arizona, US: June record consecutive days of coolest high temps

Meteorologists are reluctant to call a month "nice." They have their data and their science and typically do not describe the weather in such subjective terms.

Except now, because the data prove it.

"It's probably the best June since I've been here, and I've been here most of my life," said the National Weather Service's Valerie Meyers, who is in her late 40s. "It's been really nice."

Possibly the nicest June ever.

It's that type of thing that is fun to say but hard to quantify.

Thursday, however, was the 14th consecutive day to stay below 100 degrees. That's the longest stretch of its kind in any June since 1913.

Bizarro Earth

Strong 5.4 magnitude earthquake jolts Anchorage, Alaska, US

A strong earthquake jolted Anchorage, Alaska, on Monday, sending people diving under desks and huddling in doorways but apparently causing no damage.

The U.S. Geological Survey said an earthquake with a magnitude of 5.4 struck about 24 miles from the town of Willow at 11:28 a.m. The epicenter was 58 miles from the state's largest city, Anchorage, where the rumbling continued for several moments.

"Things were swinging pretty good and shaking, like pictures on the wall, bottles rattling - and my blood pressure went up at least 20 points," said Pam Rannals, a bartender in Talkeetna, about 30 miles from the epicenter. "We had bears in the parking lot last night and now the earthquake. Those are the talk of the town."

Bizarro Earth

Locusts Swarm Ethiopia

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© AFP/File/Tengku Bahar
Crops in large swathes of Ethiopia risk being destroyed by swarms of locusts coming from northern Somalia, the UN Office for the Coordination of Humanitarian Affairs (OCHA) said Tuesday.

The Food and Agriculture Organisation (FAO) "reports that locust swarms have been confirmed in seven regions in the country, including in areas where there is no previous record of infestation," a statement said.

"The government is expected to present a response plan specifying immediate and medium-term actions to be taken during the week," OCHA said.