Navigation path

Themes
Agriculture & food
Energy
Environment
ERA-NET
Health & life sciences
Human resources & mobility
Industrial research
Information society
Innovation
International cooperation
Nanotechnology
Pure sciences
Research infrastructures
Research policy
Science & business
Science in society
Security
SMEs
Social sciences and humanities
Space
Special Collections
Transport

Countries
Countries
  Argentina
  Australia
  Austria
  Belarus
  Belgium
  Benin
  Brazil
  Bulgaria
  Cameroon
  Canada
  Chile
  China
  Colombia
  Croatia
  Cyprus
  Czech Republic
  Denmark
  Egypt
  Estonia
  Finland
  France
  Georgia
  Germany
  Ghana
  Greece
  Hungary
  Iceland
  India
  Ireland
  Israel
  Italy
  Japan
  Kazakhstan
  Kenya
  Korea
  Latvia
  Lithuania
  Luxembourg
  Malta
  Mexico
  Montenegro
  Morocco
  Namibia
  Netherlands
  Nigeria
  Norway
  Peru
  Poland
  Portugal
  Romania
  Russia
  Senegal
  Serbia
  Slovakia
  Slovenia
  South Africa
  Spain
  Swaziland
  Sweden
  Switzerland
  Taiwan
  Tunisia
  Turkey
  Ukraine
  United Kingdom
  United States


   Infocentre

Last Update: 28-06-2012  
Related category(ies):
Environment

 

Countries involved in the project described in the article:
France  |  Switzerland
Add to PDF "basket"

Predicting hot days in Europe

'Red sky at night, shepherd's delight, red sky in morning, fisherman's warning.' This saying is one of Europe's earliest rhymes that were used to predict weather for the following day. With advances in modern technology, from radar to satellite imagery, we can now predict weather well beyond the following day. European scientists have gone one step further, however, by predicting weather, not just days and weeks in advance, but a whole season ahead. Seasonal prediction can help us prepare against adverse weather conditions in the areas of agriculture, health and other industries. The findings were published in the journal Nature Climate Change.

Predicting the next heat wave early on © Shutterstock
Predicting the next heat wave early on
©  Shutterstock

Seasonal predictions are the next hurdle faced by meteorologists but they remain a significant scientific challenge due to flow instability and nonlinearity, which occurs mostly in the mid-latitudes. In this latest study, researchers focused on whether preceding seasons rainfall allow scientists to predict the frequency of forthcoming summer hot days and physical causes of such a predictability.

Led by the Laboratoire des Sciences du Climat et de l'Environnement (LSCE) and the Swiss Federal Institute of Technology Zurich (ETH Zurich), researchers in France and Switzerland observed that summer heat in Europe rarely develops after rainy winter and spring seasons over southern Europe. But they discovered that dry seasons are either followed by hot or cold summers. What this means is that the predictability of summer heat is asymmetric and that climate projections indicate a drying of southern Europe. The results suggest that the asymmetry that exists should create a favourable situation for the development of more summer heat waves with a modified seasonal predictability from winter and spring rainfall.

The researchers noted that over the past decade Europe saw a number of exceptional summer heat waves with important impacts on society. The 2003 heat wave was the hottest summer on record since 1540 and led to a major health crisis and crop shortfall. Meteorologists were stunned when the record was shattered by the 2010 heat wave just a few years later. Maximum temperature measurements averaged over 7 days exceeding the average for this figure from 1871–2010 by 13.3 degrees Celsius. According to the researchers, extreme summers such as these could be considered as prototypes of summers of future warmer climate. But our ability to anticipate such events one or several months in advance, thereby giving us the chance to prepare ourselves, remains poor.

The team analysed precipitation and temperature observations made in 200 European meteorological stations over a period of time stretching more than 60 years. From this they made some generalisations for the region of southeastern Europe, including that rainy winters and springs inhibit the development of hot summer days for the following summer season, while dry or normal rainfalls allow either a large or a weak number of hot temperature days.

After dry months, a strong solar energy, associated with anticyclonic conditions, is transferred to the atmosphere through heat fluxes, amplifying drought and heat with a positive feedback. After rainy months, solar energy is largely used for evapo-transpiration instead, limiting the amplification of heat. Even after very dry winter and spring seasons, early summer heavy precipitations can annihilate the potential to develop extreme temperatures, which may have been the case during the 2011 summer, which followed an exceptional spring drought.


Convert article(s) to PDF

No article selected


loading


Search articles

Notes:
To restrict search results to articles in the Information Centre, i.e. this site, use this search box rather than the one at the top of the page.

After searching, you can expand the results to include the whole Research and Innovation web site, or another section of it, or all Europa, afterwards without searching again.

Please note that new content may take a few days to be indexed by the search engine and therefore to appear in the results.

Print Version
Share this article
See also

Laboratoire des Sciences du Climat et de l’Environnement (LSCE)
Nature Climate Change





  Top   Research Information Center