Using Geographic Information Systems and Remote Sensing to model site suitability for aquaculture in relation to changing climate
Neil Handisyde: Ph.D.
There is now a general consensus that climate change is a real and significant issue with its early stages being experienced in many areas. Along with other food production sectors aquaculture stands to experience a range of potential impacts in relation to changes in; temperature, solar radiation, sea surface temperature, other oceanographic variables (currents, wind velocity and wave action, etc.), sea level rise, frequency or intensity of extreme events, and water stress. Not all climate related changes will be negative for aquaculture and it is possible that changing conditions, such as warming temperatures, in some areas may actually benefit certain types of production. Ultimately successful aquaculture production at a given location depends on matching species and culture methods to a broad range of geographic, environmental, socio-economic and climatic variables. The use of Geographic Information Systems (GIS) and Remotely Sensed (RS) data provide powerful modelling tools for tackling spatial problems such as these.
The current project builds on previous climate related work within the Sustainable Aquaculture group (see image series of vulnerability of aquaculture at the national scale for Freshwater, Brackish, and Marine culture environments at right, or read a report from an earlier DFID project), and consists of a number of components:
- Global assessment of aquaculture vulnerability to changing climate at the national scale.
- GIS based 1km resolution global site suitability model for inland aquaculture under current and future climate scenarios.
- The use of MODIS data to identify surface water and patterns of flooding in Bangladesh.
- The use of multiple Landsat ETM+ images to produce a land cover map for Bangladesh.
- GIS based site suitability model for future aquaculture development in Bangladesh that incorporates the remotely sensed data outlined above along with a range of other spatial data while paying particular attention to climate variables.
This animation (at right) shows the flood cycle over an 8 year period, based on data from the Moderate Resolution Imaging
Spectroradiometer (MODIS) operated from the Terra and Aqua satellites.
The following images show other examples of the outcomes of this work:
- The image at left, below, shows Bangladesh and the proportion of time an area is inundated with water during a continuous 8 year MODIS time series.
- Sample region of Landsat ETM+ data (right, below) classified using fuzzy sets and a decision tree approach.
