About COST733

About COST 733

Motivation & Objectives

Most societal and environmental processes are influenced by weather and climate. In order to understand these connections there is often need for a “simple” characterization of the current weather. This need has increased considerably due to global warming and the challenges to study the impact of a climate change on society and environment.

Weather type classifications are simple, discrete characterisations of the current atmospheric conditions. There exists a wide collection of weather type methods, developed for different regions and for different purposes. Many of them are based on automatic, objective and consistent methods. Even though there is a long tradition for WTC, no general pan-European, objective and consistent system for weather type classifications for all Europe exist.

This was the motivation to launch COST Action 733, and the main objective of the action is to: “achieve a general numerical method for assessing, comparing and classifying weather situations in Europe, scalable to any European (sub)region with time scales between 12 h and 3 days and spatial scales of ca. 200 to 2000 km, applicable for a number of applications.”

These applications include:

frequency analysis of extreme weather events,

local climate assessment (e.g. fog/snow cover/sunshine duration),

human biometeorology and impacts on ecosystems,

climate monitoring,

assessment of impaired air quality episodes,

medium range weather forecast and climate characteristics of the forecast period (e.g. by

mapping of climate parameters related to historic weather types and application to the forecast meteorological situations),

verification of numerical weather forecast models (by checking the forecast weather types),

etc., etc.....

Secondary objectives are:

to enhance our knowledge on linkages between the atmospheric circulation, weather, climate and environmental variables,

to have an up-to-date overview of existing weather types classification methods,

to identify suitable criteria/indicators to weather types

to identify a set of useful applications of weather types classifications,

to analyse the strengths and weaknesses of the methods for different applications,

to establish a (new) scientific cooperation forum in synoptic climatology in Europe,

to provide tools for comparison and evaluation of different weather types classifications,

to assess different methodologies for the comparison of weather types classifications.

Background.

Something about the scientific background....

History

The history of COST Action 733 starts in 2004, when Dr. Ernst Dittmann (DWD) proposed a COST Action on weather types for the Technical Committee in Meteorology (TC-METEO) in COST. A working group was appointed to work out a draft MoU for such an action. The work group was led by Dr. Dittmann, and the proposed MoU succeeded to be approved by COST CSO in mid-March 2005.

The kick off meeting was organised already in April, appointing Dr, Dittmann as the first chair of the MC. The first MC-meeting was held in Utrecht (NL) 13. September 2005. The end date of the action will be 12.September 2010.

A core group was soon established, consisting of Ernst Dittman (MC-Chair). Radan Huth (MC V-chair, WG1 Chair), Paul E. James (WG2 Chair), Massimiliano Pasqui (WG3 Chair), Zbigniew Ustrnul (WG 4, Chair) and Ole Einar Tveito. From the second MC-meeting in Prague (March 2006), Ernst Dittmann retired, and Ole Einar Tveito (NO) took over as chair of the MC. In 2007 Andreas Philipp replaced Paul James as chair of WG2. Also the WG vice-chairs are now members of the core group.

Achievements

Short summary of main results