2nd International Conference on GeoComputation

Distributing Geographical Information Systems and Data Using Java and the Internet.

David R Hill

Institute of Hydrology, Crowmarsh Gifford,
Wallingford, Oxfordshire, OX10 8BB. UK
+44 (0) 1491 692461

Email: drh@ua.nwl.ac.uk

Presented at the second annual conference of GeoComputation 97 & SIRC 97, University of Otago, New Zealand, 26-29 August 1997

Abstract

Keywords
query environmental time series
spatial 4-dimensional data model
database SQL GIS Java CGI WWW
RDBMS Internet distributed

Developing efficient and effective storage and access methods for large environmental databases is one of the main research aims of the Data and Software Systems group based at the Institute of Hydrology (IH).

The Institute of Hydrology investigates the effects of landuse, climate, topography and geology on the volume and character of water resources. It focuses on understanding water and energy fluxes arising from processes such as evaporation, interception and infiltration and modelling the hydrological cycle and chemical processes above and below ground. It is the aim of the Data and Software Sys-tems group in conjunction with the scientists to design and implement software products for the dissemination of IH science. Many of these products involve the design and use of databases which are also used to manage IHs own environmental datasets. Much of the fundamental research behind IHs database designs took place in the period 1974 to 1990 during which time many of the commercial GIS packages which are in use today were not available or unable to deal with many of the problems presented by environmental datasets. As commercial GIS pack ages developed throughout the 1990s, research and development at IH moved to concentrate on environmental database design. There have been two key problems that IH has sought to ameliorate. One is that at present different data types are held in different systems making if difficult to explore relationships that span the different data types. The other is that the demand for data exceeds the IH Data Centre capacity to supply them. This paper will elaborate the problems and describe the underlying concepts involved in their solutions. It will then propose some suggestions for providing a simple query interface for environmental databases, that can be made available to remote users anywhere. The points made will be illustrated by reference to the IHs work on the Land Ocean Interaction Study (LOIS) (NERC, 1992).