Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Weather forecasts misleading due to atmospheric fluctuations?

22.03.2004


Scientists at Oxford University have discovered that small-scale fluctuations, which are wide-spread in the atmosphere, may have a greater impact on weather systems than previously thought. The results, published in Nonlinear Processes in Geophysics, may have important implications for accurate weather forecasting.



The fluctuations, known as inertia-gravity waves because they are sustained by a combination of inertial and gravitational forces, are prominent in the bottom 15 km of the atmosphere.

They can often be seen from the surface of the Earth as ’stripy’ features in clouds. Their horizontal wavelengths can be as short as 5 km – too small to be picked up by current weather prediction models, which divide the surface of the Earth into grid-boxes measuring around 50 km by 50 km.


Meteorologists have therefore always had to assume that inertia-gravity waves do not significantly interact with weather systems, such as warm and cold fronts, but this assumption had never been rigorously tested.

Motivated by the results of laboratory experiments, which seemed to challenge the meteorologists’ assumption, the Oxford scientists developed a computer model of a simple fluid system resembling the atmosphere. They represented the inertia-gravity waves as random noise in the model, since the fluctuations can be highly irregular, chaotic and transient. They found that the system could behave differently when the inertia-gravity wave representation was activated – in other words, the meteorologists’ assumptions were not always justified.

In particular, the state of the fluid could undergo spontaneous transitions to quite different states, with a dramatic shift in the patterns of low and high pressure. Extrapolation of these results to the real atmosphere suggests that inertia-gravity waves could be a cause of significant errors in weather forecasts. The surprise implication of the research is that adding random noise to the forecast might actually help improve things.

Dr Paul Williams, one of the scientists involved in the study, said: ’It seems that we have observed a phenomenon which might have the potential to affect the accuracy of weather forecasts. More research is needed to find out exactly how bad the forecast error might be, but the preliminary results are very exciting. It sounds bizarre to suggest that adding random noise to a forecast might help to improve it, but science is always full of surprises!’

Barbara Hott | alfa
Further information:
http://www.copernicus.org/EGU/npg/11/contents1.htm

More articles from Earth Sciences:

nachricht NASA's AIM observes early noctilucent ice clouds over Antarctica
05.12.2016 | NASA/Goddard Space Flight Center

nachricht GPM sees deadly tornadic storms moving through US Southeast
01.12.2016 | NASA/Goddard Space Flight Center

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

IHP presents the fastest silicon-based transistor in the world

05.12.2016 | Power and Electrical Engineering

InLight study: insights into chemical processes using light

05.12.2016 | Materials Sciences

High-precision magnetic field sensing

05.12.2016 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>