Complex science

Although there is a strong consensus that global warming is leading to major climate change, a major challenge remains in transferring the science into practical decision making environments at national level and below, particularly (though not exclusively) in developing country contexts. One of the major problems is what is known as ‘downscaling’. As the UNFCCC states, significant differences occurs at a scale below the resolution of General Circulation Models of climate change. Therefore predicting change below global levels down to sub-national and national levels where most important development decision making takes place is a core challenge. In terms of water management, this means being able to understand how GCMs can be translated into knowledge appropriate to national-level planning on future infrastructure (e.g. irrigation construction and hydropower development). As GCMs grow in complexity, more finely-grained data is becoming available, but there still remains the challenge of how to interpret and use such data. One of the key responses has been to adopt notions of no- or low-regrets solutions, which means taking investment and planning decisions now that are robust enough to withstand future variation in predicted outcomes (e.g. far higher annual precipitation in one region of a country than was originally observed in GCMs).