One of the key critiques of climate models is that they are incredibly vague. For example the 2100 precipitation change compared to the 1970-1999 baseline in Nepal is modeled to be between -30% and 100%. It is true that no certainty can be gleaned from this result, however when we are presented with a vague result such as this one it does not mean that we should not act. This result essentially means that a range of eventualities could happen in regards to future climate, all we know is that it will be different from present conditions. Not understanding the exact details of future climate is not an excuse for inaction. If actors wait until certainties were reached about every detail of future climate to act it will be too late.
It is important to acknowledge that although climate models may not be able to tell us exactly what the impact of climate change will be on rainfall in Nepal in 100 years there are certain aspects of the climate system that can be forecasted. For example the models have reached a more concrete result in regards to the 2100 temperature change in Nepal. Temperatures will rise between two and six degrees celcius. The difference in temperature rise can be attributed to different emission scenarios. We know that the temperature in Nepal will rise, moreover it will rise at a rate greater than worldwide warming. In multi model projections there are certain areas in which most models agree about the outcomes. These outcomes are not generated by indigestible formulas, but rather by fundamental physics. We know the climate is warming and we know it will continue to warm. The question remains as to how much warming we will experience. Climate models do produce some certainties.
When addressing climate models in Nepal one may consider the work done by the Integrated Development Society Nepal. A study done on agriculture and the impacts of future climate change illuminated food security issues in Nepal. The study acknowledges the uncertainties and limits of their findings, stating that a more comprehensive study of agriculture in Nepal would prove useful. Their findings specifically concerning rice, maize and wheat are informative. Rice makes up 20% of the agricultural GDP in Nepal and 50% of the caloric intake. The study finds that that in the terai and hill regions there will be short term increases in the growing season. The terai will likely experience long term decreases in yields, there are mixed results in the hills. However in the mountains the short and long term yields will likely be increased. Although the results of the study are not completely certain the outcome tells us that there will be significant changes in where crops are grown in the future. This will likely result in land use change and possible migration and livelihood change.
Perhaps the greatest lesson that we can glean from climate models is that the climate is changing in complex ways and there is a large amount of uncertainty about the future of our climate. Action must be taken to address this threat. The focus must be on building resilience to stresses that the climate system may place on civilization. Although a government may not always be able to address a specific threat systems may be built up to respond to a diverse set of threats.