Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Illinois professor to address global warming at book launching

10.05.2006


Michael Schlesinger, a professor of atmospheric sciences at the University of Illinois at Urbana-Champaign, will participate in news conferences in New York City on May 9, and Washington, D.C., on May 10, publicizing the U.S. debut of the book "Avoiding Dangerous Climate Change."

Published by Cambridge University Press, the book builds upon scientific findings presented at the "Avoiding Dangerous Climate Change" conference held in Exeter, England, in February last year. The conference was sponsored by the United Kingdom Department of Environment, Food and Rural Affairs.

The conference brought together more than 200 scientists and political leaders from 30 nations. Major themes included key vulnerabilities of the climate system and critical thresholds, socio-economic effects, and technologies to limit greenhouse-gas emissions.



Based on his talk at the conference, Schlesinger contributed a book chapter titled "Assessing the Risk of a Collapse of the Atlantic Thermohaline Circulation."

Higher temperatures caused by global warming could add fresh water to the northern North Atlantic Ocean by increasing the precipitation and by melting nearby sea ice, mountain glaciers and the Greenland ice sheet, Schlesinger said. This influx of fresh water could reduce the surface salinity and density, leading to a shutdown of the thermohaline circulation.

"We have evidence dating back to 1965 that shows a drop in salinity around the North Atlantic," Schlesinger said. "So far, the salinity change is small, but we could be standing at the brink of an abrupt and irreversible climate change."

Among the talking points Schlesinger will cover at the news conferences:

  • The observed warming during 1856-1990 was predominantly human-induced. "Using a simple climate/ocean model, we calculated the contributions to the observed changes in global-mean, near-surface temperature caused by human and volcano forcing, and putative variations in the irradiance of the sun for the years 1856-1990," Schlesinger said. "We found the human effect has steadily increased and is now the dominant external factor. Variations in solar output played only a minor role in the observed temperature change, and we found no significant contribution from volcanoes."

  • The observed melting of alpine glaciers, the Greenland and West Antarctic ice sheets, the freshening of the North Atlantic Ocean, and the slowdown of the Atlantic thermohaline circulation are the "smoking gun" of global warming. "We are seeing dangerous, human-induced climate change," Schlesinger said. "The melting of the Greenland ice sheet would raise sea level by 18 feet. Melting of the Antarctic ice sheet would raise sea level an additional 22 feet. Most coastal cities would be inundated."

  • These observed changes in climate and ongoing research have shown that human-induced warming is proceeding more quickly than anticipated. "Not only are the Greenland and Antarctica ice sheets melting much faster than models predicted, measurements show a significant freshening (influx of fresh water) of the North Atlantic Ocean and a 30 percent reduction of North Atlantic circulation within the past 50 years," Schlesinger said. "What we are seeing is very worrisome. It is now clear that we have no time to spare -- we must act immediately."

  • If the present course of increasing emissions continues, there is a high likelihood that the Atlantic thermohaline circulation will shut down during the next 200 years. The thermohaline circulation is driven by differences in seawater density, caused by temperature and salinity. Like a great conveyor belt, the circulation pattern moves warm surface water from the southern hemisphere toward the North Pole. Between Greenland and Norway, the water cools, sinks into the deep ocean, and begins flowing back to the south.

"This movement carries a tremendous amount of heat northward, and plays a vital role in maintaining the current climate," Schlesinger said. "If the thermohaline circulation shut down, the southern hemisphere would become warmer and the northern hemisphere would become colder. The heavily populated regions of eastern North America and western Europe would experience a significant shift in climate."

Two major factors affect the range of possible future temperature increases: Scientists don’t know precisely how sensitive the climate system will be to future emissions; and they don’t know exactly how much humankind will emit. People can only control one of the factors. By reducing emissions, the amount of future warming and associated impacts can be reduced.

"Recent work by five independent research teams has shown that climate sensitivity could be larger than the 4.5 degrees Celsius upper bound published by the Intergovernmental Panel on Climate Change," Schlesinger said. "In fact, climate sensitivities as high as 9 degrees Celsius are not implausible. Paralysis in near-term action to significantly reduce emissions could make mitigation nearly impossible to attain."

Two other authors and one of the book’s editors will also participate in the news conferences. The May 9 news conference will begin at noon EDT at JP Morgan-Chase corporate headquarters in Manhattan. The May 10 news conference will begin at 4 p.m. in Room 485 of the Russell Senate Office Building.

James E. Kloeppel | EurekAlert!
Further information:
http://www.uiuc.edu

More articles from Earth Sciences:

nachricht In times of climate change: What a lake’s colour can tell about its condition
21.09.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)

nachricht Did marine sponges trigger the ‘Cambrian explosion’ through ‘ecosystem engineering’?
21.09.2017 | Helmholtz-Zentrum Potsdam - Deutsches GeoForschungsZentrum GFZ

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: LaserTAB: More efficient and precise contacts thanks to human-robot collaboration

At the productronica trade fair in Munich this November, the Fraunhofer Institute for Laser Technology ILT will be presenting Laser-Based Tape-Automated Bonding, LaserTAB for short. The experts from Aachen will be demonstrating how new battery cells and power electronics can be micro-welded more efficiently and precisely than ever before thanks to new optics and robot support.

Fraunhofer ILT from Aachen relies on a clever combination of robotics and a laser scanner with new optics as well as process monitoring, which it has developed...

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Fraunhofer ISE Pushes World Record for Multicrystalline Silicon Solar Cells to 22.3 Percent

25.09.2017 | Power and Electrical Engineering

Usher syndrome: Gene therapy restores hearing and balance

25.09.2017 | Health and Medicine

An international team of physicists a coherent amplification effect in laser excited dielectrics

25.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>