Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Overconfidence leads to bias in climate change estimations

19.12.2006
Just as overconfidence in a teenager may lead to unwise acts, overconfidence in projections of climate change may lead to inappropriate actions on the parts of governments, industries and individuals, according to an international team of climate researchers.

"Climate researchers often use a scenario approach," says Dr. Klaus Keller, assistant professor of geosciences, Penn State. "Nevertheless, scenarios are typically silent on the question of probabilities."

The Intergovernmental Panel on Climate Change, which is in its third round of climate assessment, uses models that scenarios of human climate forcing drive. These forcing scenarios are, the researchers say, overconfident.

"One key question is which scenario is likely, which is less likely and which they can neglect for practical purposes," says Keller who is also affiliated with the Penn State Institutes of Energy and the Environment. "At the very least, the scenarios should span the range of relevant future outcomes. This relevant range should also include low-probability, high-impact events."

The researchers provide evidence that the current practice neglects a sizeable fraction of these low probability events and results in biased outcomes. Keller; Louis Miltich, graduate student; Alexander Robinson, Penn State research assistant now on a Fulbright Fellowship in Berlin, and Richard Tol, senior research officer, Economic and Social Research Institute, Dublin, Ireland, developed an Integrated Assessment Model to derive probabilistic projections of carbon dioxide emissions on a century time scale. Their results extended far beyond the range of previously published scenarios, the researchers told attendees today (Dec. 15) at the fall meeting of the American Geophysical Union in San Francisco.

Noting that overconfidence is an often observed effect, Keller cites a study reviewing estimates of the weight of an electron as an example. The reported range for the weight of an electron from 1955 to the mid-1960s did not include the weight considered correct today. On a more closely related topic, the range of energy use projections in the 1970s typically missed the observed trends.

"We need to identify key sources of overconfidence and critically reevaluate previous studies," says Keller.

According to their study, past scenarios of carbon dioxide emissions can miss as much as 40 percent of probabilistic projection, missing a large number of low-probability events. The omitted scenarios may include low-probability, high-impact events.

"If low-probability, high-impact events exist, such as threshold responses of ocean currents or ice sheets, omitting these scenarios can lead to poor decision making," says Keller. "We need to see the full range of possible scenarios, because the actual outcome may not be contained in the central estimate.

"New tools and faster computers enable a considerably improved uncertainty analysis," he adds. "If you do not tell how likely the probability of a scenario is, people are left to guess. A sound scientific analysis can at least tell how consistent these guesses are with the available observations and simple, but transparent assumption."

A'ndrea Elyse Messer | EurekAlert!
Further information:
http://www.psu.edu

More articles from Earth Sciences:

nachricht Strong storms generating earthquake-like seismic activity
16.10.2019 | Florida State University

nachricht The shelf life of pyrite
14.10.2019 | MARUM - Zentrum für Marine Umweltwissenschaften an der Universität Bremen

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Solving the mystery of quantum light in thin layers

A very special kind of light is emitted by tungsten diselenide layers. The reason for this has been unclear. Now an explanation has been found at TU Wien (Vienna)

It is an exotic phenomenon that nobody was able to explain for years: when energy is supplied to a thin layer of the material tungsten diselenide, it begins to...

Im Focus: An ultrafast glimpse of the photochemistry of the atmosphere

Researchers at Ludwig-Maximilians-Universitaet (LMU) in Munich have explored the initial consequences of the interaction of light with molecules on the surface of nanoscopic aerosols.

The nanocosmos is constantly in motion. All natural processes are ultimately determined by the interplay between radiation and matter. Light strikes particles...

Im Focus: Shaping nanoparticles for improved quantum information technology

Particles that are mere nanometers in size are at the forefront of scientific research today. They come in many different shapes: rods, spheres, cubes, vesicles, S-shaped worms and even donut-like rings. What makes them worthy of scientific study is that, being so tiny, they exhibit quantum mechanical properties not possible with larger objects.

Researchers at the Center for Nanoscale Materials (CNM), a U.S. Department of Energy (DOE) Office of Science User Facility located at DOE's Argonne National...

Im Focus: Novel Material for Shipbuilding

A new research project at the TH Mittelhessen focusses on the development of a novel light weight design concept for leisure boats and yachts. Professor Stephan Marzi from the THM Institute of Mechanics and Materials collaborates with Krake Catamarane, which is a shipyard located in Apolda, Thuringia.

The project is set up in an international cooperation with Professor Anders Biel from Karlstad University in Sweden and the Swedish company Lamera from...

Im Focus: Controlling superconducting regions within an exotic metal

Superconductivity has fascinated scientists for many years since it offers the potential to revolutionize current technologies. Materials only become superconductors - meaning that electrons can travel in them with no resistance - at very low temperatures. These days, this unique zero resistance superconductivity is commonly found in a number of technologies, such as magnetic resonance imaging (MRI).

Future technologies, however, will harness the total synchrony of electronic behavior in superconductors - a property called the phase. There is currently a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Symposium on Functional Materials for Electrolysis, Fuel Cells and Metal-Air Batteries

02.10.2019 | Event News

NEXUS 2020: Relationships Between Architecture and Mathematics

02.10.2019 | Event News

Optical Technologies: International Symposium „Future Optics“ in Hannover

19.09.2019 | Event News

 
Latest News

Energy Flow in the Nano Range

18.10.2019 | Power and Electrical Engineering

MR-compatible Ultrasound System for the Therapeutic Application of Ultrasound

18.10.2019 | Medical Engineering

Double layer of graphene helps to control spin currents

18.10.2019 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>