Mesoscale Alpine Climate (MAC)
Christoph Frei, Climate Research ETH, Zurich, Switzerland
Christian Häberli, MeteoSwiss, Zurich, Switzerland
Inga Groehn, Dept. of Meteorology and Geophysics, University of Vienna,
Austria
Carlo Cacciamani, ARPA-SMR, Bologna, Italy
What are the mesoscale features of the climate in the Alpine region? Have these features changed over the last century, and can
we understand the variations in terms of the in-situ physical processes and variations of the atmospheric circulation?
These questions have become of increasing interest for the understanding of regional climate variations and the assessment of future
regional climate change. A new scientific program on Mesoscale Alpine Climate (MAC) is currently planned as a spin-off activity of MAP.
MAC aims at the quantitative description, the basic understanding, and the improvement of prediction capabilities of the Alpine climate
by means of a coordinated use of observations from the entire region.
Introduction and Motivation
The idea for a coordinated research initiative on Alpine climate emerged at a two-day workshop held in Interlaken in Spring 2000.
The workshop brought together climate scientists and representatives from weather services and other monitoring institutions in
the Alpine region. Apart from the scientific exchange between the participants several workshop discussions were held to develop
scientific visions of and practical options for an improved exploitation of non-GTS data for climate research. It was recognised that
the competence in regional climate research, the awareness of data quality issues at the monitoring centres, and the availability
of dense and long-range observations are outstanding, and that the community could improve its world-wide significance for
mountain climate research by the coordination of competence, the joint development of tools, and the improved use of data.
The MAC initiative builds upon activities within the Mesoscale Alpine Program. Actually the initiative is mainly put forth by
members of the MAP working groups on `Routine Network Data' and `Alpine Climatology'. Its scientific aims are related to and
extend the supporting objective of MAP for a
`Mesoscale Alpine Climatology'. The idea of Alpine-wide exchange of non-GTS data is motivated by achievements within MAP.
However the new activities require the involvement of scientific communities which have not directly participated in MAP and the
extension of data exchange to the sector of climate data demands new approaches. MAC is therefore conceived as a spin-off project of MAP.
Following the workshop, a core group of scientists and representatives from weather services has prepared a draft MAC Design
Proposal. The document outlines the scientific objectives of the programme and describes a new technical solution for data
exchange, which takes into account the desirability for both, easy access and protection of property rights. The document is
subject to final revisions and will soon be distributed for a broader review.
Figure 1. Precipitation fields (mm per day) for a selection of particularly
wet October months in the Lago-Maggiore region,
as derived from a
consistent centennial reconstruction. (Courtesy Jürg Schmidli, ETH Zurich.)
Scientific Objectives
Three scientific objectives constitute the overall guideline of the program. These are to:
- establish a climatology of surface weather and mesoscale circulation phenomena in the Alpine region, including measures
of temporal variability and the occurrence of extreme events;
- quantify the climate variations observed during the instrumental period in the Alpine region and advance the understanding
of these variations in relation to mesoscale and synoptic-scale circulation, global teleconnections,
and anthropogenic forcings;
- validate and improve numerical and statistical methods for the seasonal prediction and the estimation of future changes of
regional Alpine climate and climate impacts.
Progress along these lines will be sought by following a set of major scientific tasks, embracing:
- the development of techniques (data quality control, homogenisation, objective analysis);
- the derivation of consistent Alpine-wide data products (climatologies, mesoscale centennial objective analyses of
upper-air and surface parameters, see example in Figure 1);
- the application of these products (statistical analyses and model evaluation).
Particular emphasis in all three objectives will be given to extreme events.
Data Exchange
The transfer of climate data from the monitoring institutions to the research projects shall be organised by means of a
Data Exchange Platform (DEP). In contrast to the MAP Data Centre, the DEP will not be set-up as a centralised database,
but as an information platform facilitating the application procedure and data delivery. The DEP shall carry detailed information
on climate data archives at individual monitoring services (station inventories, parameters and observation periods), and graphical
tools to effectively view this information. Moreover, it will provide guidelines on the application procedure (contact points,
forms, response times) and list an agreed set of conditions under which the exchange can be approved. The common set of rules will
substantially accelerate current practice in climate data exchange while the data provider keeps control over the external use
of its property. Important practical advantages of this solution are the flexibility with respect to updates and quality improvements
by the data owner and the comparatively low costs for implementation and maintenance.
Options for funding
Several sources are considered for acquiring funding for the MAC program: For research activities national science funds of the
Alpine countries and the European Union RTD funds are reasonable options. These options are discussed within the MAC core group
at present. For the technical and operational activities of MAC (establishment and maintenance of the data exchange platform,
operation of the program office), the core group has decided to seek funding from the National Weather Services in the Alpine
region through the European Climate Support Network (ECSN), a programme of the European Weather Services Network (EUMETNET).
Activities along these lines are put forth in close collaboration with MeteoSwiss, the actual responsible member of ECSN.
© MAP Data Centre - March '01 - MAP WebMaster