Details

Large progress has been made in the past few years towards quantifying and understanding climate variability during past centuries. Both the understanding of the past and the knowledge of the processes are important for assessing and attributing the anthropogenic effect on present and future climate. The most important time period in this context is the past 100 years, which comprises both large natural variations and extremes as well as anthropogenic influences, most pronounced in the past few decades.

The aim of the workshop is to bring scientists working on data issues together with statistical climatologists, modellers, and atmospheric chemists to discuss gaps in our understanding of climate variability during the past ~100 years.

The workshop will cover four topical sessions:

1. Extending the observational record

Talks will cover the whole range of data types: meteorological and chemical, surface and upper-air, solar and volcanic data, spanning everything from water vapour to wind, with a focus on data sets that cover much or all of the 20th century. Presentations in this session should focus on data-related issues such as quality, coverage, resolution, errors, and future developments. Reanalyses and reconstructions are also included in this session

2. Climate variability, trends, and large-scale modes

This session is aimed at statistical studies on climate variability and large-scale modes. Variability will be addressed on different scales, from global and hemispheric studies to regional climate studies. Climate variability modes such as El Nino / Southern Oscillation, the North Atlantic Oscillation, the Pacific-North American pattern, and Indian monsoon changes are also included. An important aspect of the session is to combine observational and modeling studies. Subtopics include: Observed global and hemispheric trends, modeled trends and attribution, climate variability in the tropics, the North Atlantic-European sector, the Pacific-North American sector, the Arctic, Northern Asia, the southern hemisphere, Antarctica.

3. Climate Extremes

Climatic extremes are of special relevance because of their large impact on society, economy, and ecosystems. Changes in extremes (frequency, magnitude) are most carefully looked at with respect to global change. In this session, climatic extremes in the 20th century such as droughts, floods, strong El Ninos, and volcanic eruptions are discussed. Again, we seek studies that combine model simulations with observations. Possible subtopics are: North American droughts, Sahel droughts, early 20th century Arctic warming, heat waves, European floods, extreme El Ninos, volcanic eruptions.

4. Chemical climate variability and the stratosphere

This session focuses on chemical climate variability and on stratospheric dynamics in the context of 20th century climate variability. Possible subtopics include: Changes in the polar vortex, stratospheric ozone and its interaction with climate variability, solar effects on the stratosphere, solar effects at the surface and in the troposphere, tropospheric ozone, tropospheric chemistry and climate variability, aerosols, water vapour.

Conference board:

Stefan Broennimann, ETH Zurich
Juerg Luterbacher, University of Bern
Henry Diaz, NOAA/ESRL
Richard Stolarski, NASA/GSFC
Urs Neu, ProClim-
Tracy Ewen, ETH Zurich