Geoscience Reference
In-Depth Information
The operability of the GTS is dependent on data exchange and a related policy
of data holders. Today, each National Meterological and Hydrological Service
(NHMS) has its own data access policy ranging from free access to highly
commercially oriented data selling. Even within the European Union (EU),
meteorological data policy is quite heterogenous and the exchange of data between
NMHS, apart from for weather forecast purposes, such as for climate monitoring, is
sometimes limited. Generally, important information on meteorological data is
provided in table or map form by basic metadata of the station network, which
provides information about location, geographical coordinates, altitude, sensor
equipment and data availability, etc., without any charge from NMHS. Easy access
to such information is still not guaranteed, but there is a move towards providing a
greater amount of information without restriction.
In Europe, the idea of spatial data infrastructure (SDI) was substantially
supported by the INSPIRE (http://inspire.jrc.it/home.html) initiative. INSPIRE is an
EU directive that forces EU member states to provide spatial data to different users
according to OGCs SDI standards. As a result of INSPIRE and as a general need of
climate research, European NMSs started with efforts to meet INSPIRE needs.
Within the frame of EUMETNET, the EUROGRID was formulated with its first
step as a showcase (S-EUROGRID, see www.eurogrid.eu, [KLE 08]). EUROGRID
aims to provide a SDI for climate data according the OGC standards. In addition to
this multinational initiative, climatological/meteorological SDIs were established on
national levels. SeNorge, a common meteorological and hydrological effort in
Norway, is a good example (www.senorge.no). Due to the user-friendly data policy
in Norway, SeNorge not only displays climate data fields on a monitor screen
according to the OGS WMS (Web Map Service) standard, but users can also obtain
and integrate data of interest according to the WFS (Web Feature Service) and WCS
(Web Coverage Service) standard. These OGC standards for web-mapping have
received substantial interest in the field of meteorology over the last few years.
Another well-established OGC standard used in addition to meteorological and
climatological applications is the Google Earth KML format for many web services.
Integration of OGC-compliant spatial infrastructure for distribution of climate data
received much earlier support in the USA compared with Europe. The NOAA
(National Oceanic and Atmospheric Administration), and in particular NCAR
(National Centre for Atmospheric Research), supported the OGC ideas of
interoperability for meteorological data. Special attention was given to the ArcGIS
Atmospheric Data Model, a collaborative initiative among ESRI, UCAR, NCAR,
Raytheon, Unidata, and NOAA. The ArcGIS Atmospheric Data Model aims to
represent each of these data objects in a uniform manner, enabling their
superposition and combined analysis in the ArcGIS desktop environment. For the
first time, the ArcGIS 9.2 [ESR 09] release supported both the NetCDF and HDF-5
data format through a new tool from the ArcGIS toolbox list. Both the NetCDF and
HDF data models are commonly used in atmospheric sciences, e.g. data fields from
climate model runs are available in NetCDF. Through this data model, a
fundamental linkage between the GI community and atmospheric sciences
community was established.
