The topic working group on ‘spatial analysis and modelling’ (SAM) from the Challenge Program for Water and Food (CPWF) has agreed on a partnership between the International Water Management Institute (IWMI), Cornell University and Texas A&M University on a product dealing with global climate reanalysis data.

This partnership and announced its intentions at the recent Soil and Water Technology (SWAT) 2012 conference. The product (available at this address: http://tamu-cornell.drfuka.org/) will be hosted by Texas A&M University for now.

As an upcoming paper highlights, “Obtaining representative or near real-time meteorological data to force watershed models can be difficult and time consuming. Land based stations are often too far from the point of interest to adequately represent the weather, and many have  gaps in the data series.” The Climate Forecast System Reanalysis (CFSR) global meteorological data set has the advantage of using precipitation and temperature data, which generally provide better predictions of watershed discharge than land based stations at distances greater than 10 km from the watershed center.

This data set is useful for the SAM team for hydrological modeling, in the absence of gauge data. However, the data can also be used for any other application. It requires MET parameters – a lot of other parameters were not included (see full details at: http://rda.ucar.edu/pub/cfsr.html). Daniel Fuka, PhD student from Cornell University is leading this work.

Terraces in Debre Libanos

Terraces - a possible application for spatial analysis and modeling (Photo credit: ILRI/Ewen Le Borgne)

What does hydrological modeling offer when analyzed together with human land and landscape interventions? Where does it lead and how practical can it be? This was the focus of a podcast on spatial analysis and modeling work undertaken mainly in the Nile Basin Development Challenge.

As part of the Challenge Programme for Water and Food, Peter Casier interviewed Catherine Pfeifer, a post-doctoral scientist working for the International Livestock Research Institute (ILRI) and the International Water Management Institute (IWMI) in Addis Ababa, Ethiopia.

In this podcast (3’42’’), Catherine explains that, as compared with Geographic Information Systems (GIS), spatial analysis and modeling (SAM) work does not limit itself to being a useful tool – it actually focuses on what is planned with the data collected and how to analyze it for what purpose. In addition, it is not just hydrological modeling but it works in combination with emergent understanding of how human systems define and shape their landscape and land interventions. The combination of biophysical and human perspectives adds the richness to the work of the SAM topic working group.

In practice, this work can prove very useful for predicting the impact of a given landscape intervention to it hydrology. Pfeifer mentions the case of terraces where spatial analysis and modeling helps estimate how terraces might impact water flow and the potential benefits to the farmers in the future (improved productivity, reduced erosion etc.).

In other settings too, spatial analysis and modeling should help inform extension services and farmers about the potential benefits and drawbacks of different interventions for water and land management, placing the work of the CPWF SAM group at the centre of the rationale behind the Challenge Programme for Water and Food.