Featured Research

from universities, journals, and other organizations

European winter weather harder to forecast in certain years

Date:
May 15, 2013
Source:
National Oceanography Centre
Summary:
Weather forecasters have a tougher job predicting winter conditions over Europe in some years over others, concludes a new study.

Widespread snowfall in the UK in December 2010.
Credit: Credit NASA / Jeff Schmaltz

Weather forecasters have a tougher job predicting winter conditions over Europe in some years over others, concludes a new study carried out by the National Oceanography Centre.

The study revealed that the relationship between our winter weather and the strength of the airflow coming in from the Atlantic -- one of the factors used by forecasters to predict the weather -- is stronger in some years than others. The results were recently published in the Royal Meteorological Society publication Weather.

Co-authors Drs Joël Hirschi and Bablu Sinha from the National Oceanography Centre explain: "There are two major atmospheric pressure systems centred around Iceland and the Azores that are very influential for the weather in Europe. Air flows between these two systems, bringing mild air from the North Atlantic to Europe. The pressure difference between the two pressure systems -- and the corresponding airflow -- fluctuates and scientists call this phenomenon the 'North Atlantic Oscillation', or NAO, which is by convention positive when the pressure difference is a stronger than average and negative when it is weaker than average.

"When there is more air coming from the Atlantic, we get milder, wetter winters, as in 2007 and 2008. And when the airflow is weaker, our weather is influenced by air masses from Siberia and the Arctic, bringing colder and drier conditions."

But the scientists wanted to know how reliable the relationship is between the pressure systems over Iceland and the Azores, and European weather. The results show that when the airflow is weaker -- due to a smaller pressure difference between the two systems -- European weather is harder to predict than when it is stronger.

"It's like a guitar string," says Dr Hirschi. "When there is tension in the string, it stays straight. If you slacken the tension enough, the string goes wobbly.

"So when we have a vigorous airflow driven by a large pressure difference, it tends to stay straight and the weather is easy to define. When weaker, the airflow meanders, leading to more complicated weather patterns. You get big differences in weather over Europe, switching between cold Arctic/Siberian air masses, and milder subtropical air masses. This is why in December 2010, the UK suffered from low temperatures and heavy snowfall, while other European regions such as the Balkans experienced warm and wet conditions."

In this study, the researchers looked at the strength of the NAO during each year between 1880 and 2009 and compared this with observations of winter weather conditions over the same period.


Story Source:

The above story is based on materials provided by National Oceanography Centre. Note: Materials may be edited for content and length.


Journal Reference:

  1. Roger Heape, Joël Hirschi, Bablu Sinha. Asymmetric response of European pressure and temperature anomalies to NAO positive and NAO negative winters. Weather, 2013; 68 (3): 73 DOI: 10.1002/wea.2068

Cite This Page:

National Oceanography Centre. "European winter weather harder to forecast in certain years." ScienceDaily. ScienceDaily, 15 May 2013. <www.sciencedaily.com/releases/2013/05/130515085226.htm>.
National Oceanography Centre. (2013, May 15). European winter weather harder to forecast in certain years. ScienceDaily. Retrieved September 30, 2014 from www.sciencedaily.com/releases/2013/05/130515085226.htm
National Oceanography Centre. "European winter weather harder to forecast in certain years." ScienceDaily. www.sciencedaily.com/releases/2013/05/130515085226.htm (accessed September 30, 2014).

Share This



More Earth & Climate News

Tuesday, September 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Earth Has Lost Half Its Vertebrate Wildlife Since 1970: WWF

Earth Has Lost Half Its Vertebrate Wildlife Since 1970: WWF

Newsy (Sep. 30, 2014) — A new study published by the World Wide Fund for Nature found that more than half of the world's wildlife population has declined since 1970. Video provided by Newsy
Powered by NewsLook.com
Seismic Activity Halts Recovery at Japan Volcano

Seismic Activity Halts Recovery at Japan Volcano

AP (Sep. 30, 2014) — Rescuers were forced to suspend plans to recover at least two dozen bodies from near the summit of Mount Ontake in central Japan on Tuesday after increased seismic activity raised concern about the possibility of another eruption. (Sept. 30) Video provided by AP
Powered by NewsLook.com
Dolphins Might Use Earth's Magnetic Field As A GPS

Dolphins Might Use Earth's Magnetic Field As A GPS

Newsy (Sep. 30, 2014) — A study released Monday suggests dolphins might be able to sense the Earth's magnetic field and possibly use it as a means of navigation. Video provided by Newsy
Powered by NewsLook.com
How To Battle Stink Bug Season

How To Battle Stink Bug Season

Newsy (Sep. 30, 2014) — Homeowners in 33 states grapple with stink bugs moving indoors at this time of year. Here are a few tips to avoid stink bug infestations. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins