It is well known in the scientific community that climate change will impact humans in several ways depending on their location. However, the myriad of complex decision patterns for human reaction to climate change and the variability of regional impact often limits scientific analysis to qualitative analysis of the consequences of climate change. In response to this trend of study, Samson et al. (2011) studied the relationship between global distributions of human population density and climate to predict future regional climate vulnerabilities. Niche models were used to create this global index of the projected impacts of climate change on human populations by assessing how environmental niches would likely change or move based on shifts in climate. Human population density data were obtained from the Gridded Population of the World and then adjusted to United Nations national population size records, while climate forecast was taken from the WorldClim database. From these data, researchers identified Central America, Central South America, the Arabian Peninsula, Southeast Asia, and much of Africa as the regions whose populations are most vulnerable to the effects of climate change. Notably, these regions are far away from the high-latitude areas where it is estimated that climate change will be the greatest. The research also employed geographically weighted regression models to conceptualize the spatial element of the relationship between climate and humans. – Adriane Holter
Samson, J., Berteaux, D., McGill, B. J., Humphries, M. M., 2011. Geographic Disparities and moral hazards in the predicted impacts of climate change on human populations. Global Ecology and Biogeography published ahead of print February 17, 2011,doi: 10.1111/j.1466-8238.2010.00632.x
The ecological niche model used in this projection was contrasted with CO2 emissions data to quantitatively discern the concept of a moral hazard in climate change. This moral hazard reflects the relationship of the cause for and the predicted consequences of climate change. Interestingly, researchers found that the human populations that created the largest amount of greenhouse gases on a per capita basis were the least likely to experience the most severe effects of climate change. Researchers also found that the factors that cause regional climate change are correlated with the projected impact of climate change on human populations. Thus, a moral hazard exists on the level that those populations that produce the most green-house gas transmit the harmful byproduct onto other populations.
The research supports the intuitive theory that areas of the globe that are already dry will increase in dryness and become increasingly vulnerable. One reason for this vulnerability is the difficulty of food production in agricultural and pastoral societies when dryness decreases the amount of arable land. Conversely, cold areas with low population densities will be able to support larger future populations with the impact of climate change. It is extremely likely that climate change will result in new dispersals of human populations throughout the globe; however, we must also ask if reduced population densities in a given location are due to the inability of humans to live there or because they elect to leave. Regardless, these conclusions support the need for climate policy that responds to the predicted needs of those populations that will be most greatly influenced by climate change.