Chapter 1
Introduction
H.-J. Bolle
The project of the European Commission on "Research into 'Global Change' in the
Mediterranean: A regional network" (RICAMARE) is part of the programme
"European Network for Research into Global Change" (ENRICH). In February 2001
it organized with the support of IGPB-START and CNES a workshop on the
"Assessment, assimilation, and validation of data for 'Global Change' related
research in the Mediterranean area". Part of this workshop was dedicated to the
analysis of long time series of meteorological data to document the variability of
climate in the Mediterranean region and to quantify trends.
In parallel the workshop on "Development of Priority Climate Indices for Africa:
A CCIICLIVAR Workshop of the WorldMeteorological Organization and the World
Climate Research Programme" was held, organized by WMO and the CCIICLIVAR
Working Group on Climate Change Detection jointly with the Direction Nationale
de la Meteorologie of Morocco which hosted both workshops. Thanks the
contribution from this workshop in addition the present trends at many African
stations could be included. This provides a unique data base for the whole
Mediterranean and African area to diagnose present climate variability and climatic
trends and to measure the accuracy of its simulation by climate models.
Because the results of these numerical simulations by climate models are called
"data" as well, it is emphasized that the part of the workshop which dealt with climate
variability primarily focussed on measured (and in one case proxy) data. In fact the
Earth system can be described in different ways: by empirical data, to which since a
few decades also observations from space must be counted, and by numerical
simulations which produce an alternative data set.
The different ways to look at the Earth system generate different worlds: The
model world, in which data are generated according to mathematical rules in strictly
predefined geographical projections, the world based upon physical and chemical in
situ measurements, where data are generated more or less at random at the ground and
in the air, the world that retrospectively is reconstructed from proxy data, and the
world inferred from remotly sensed signals received in space with more or less
perfect coverage but afflicted with measuring and interpretation errors. In operational
networks meteorological quantities are measured under specific controlled conditions
which may not be fully representative of the surrounding landscape. Measured data
sets provide us with certain information about the behaviour of nature in specitic
spots and models provide us with a laboratory to study how nature would react to
specific forcing if it would have been constructed like the models. Climate research
Introduction
H.-J. Bolle
The project of the European Commission on "Research into 'Global Change' in the
Mediterranean: A regional network" (RICAMARE) is part of the programme
"European Network for Research into Global Change" (ENRICH). In February 2001
it organized with the support of IGPB-START and CNES a workshop on the
"Assessment, assimilation, and validation of data for 'Global Change' related
research in the Mediterranean area". Part of this workshop was dedicated to the
analysis of long time series of meteorological data to document the variability of
climate in the Mediterranean region and to quantify trends.
In parallel the workshop on "Development of Priority Climate Indices for Africa:
A CCIICLIVAR Workshop of the WorldMeteorological Organization and the World
Climate Research Programme" was held, organized by WMO and the CCIICLIVAR
Working Group on Climate Change Detection jointly with the Direction Nationale
de la Meteorologie of Morocco which hosted both workshops. Thanks the
contribution from this workshop in addition the present trends at many African
stations could be included. This provides a unique data base for the whole
Mediterranean and African area to diagnose present climate variability and climatic
trends and to measure the accuracy of its simulation by climate models.
Because the results of these numerical simulations by climate models are called
"data" as well, it is emphasized that the part of the workshop which dealt with climate
variability primarily focussed on measured (and in one case proxy) data. In fact the
Earth system can be described in different ways: by empirical data, to which since a
few decades also observations from space must be counted, and by numerical
simulations which produce an alternative data set.
The different ways to look at the Earth system generate different worlds: The
model world, in which data are generated according to mathematical rules in strictly
predefined geographical projections, the world based upon physical and chemical in
situ measurements, where data are generated more or less at random at the ground and
in the air, the world that retrospectively is reconstructed from proxy data, and the
world inferred from remotly sensed signals received in space with more or less
perfect coverage but afflicted with measuring and interpretation errors. In operational
networks meteorological quantities are measured under specific controlled conditions
which may not be fully representative of the surrounding landscape. Measured data
sets provide us with certain information about the behaviour of nature in specitic
spots and models provide us with a laboratory to study how nature would react to
specific forcing if it would have been constructed like the models. Climate research