Before they can determine where the hotspots are in the world demographers must have other information about the population besides how many people live in a region. For instance, they need to know how old the people are, what proportion of the population are women and children, how much individuals earned in the population and other pertinent information to determine how much of an impact climate change will have on them. At the same time they must have information about the geological region such as rainfall amount, land elevation above sea level, and the availability of natural resources such as food and water. All this information is needed to determine how vulnerable or resilient a population would be to climate changes in the region.

For example, people in London would respond to flooding differently from people living in poor cities in the low lying areas of Bangladesh because of the availability of resources to help them. The availability of data from high income areas like London makes it easier for demographers to make pretty good predictions on how an area would respond to environmental impacts such as flooding, earthquakes, etc, while on the other hand; they would not have adequate data to make good predictions on the impact of these events in a poor region. It is here in these poor regions where global climate changes will mostly be felt. But the problem with demographic data collected by researchers is that the data is usually applied on a national level and not on a smaller city level.

Demographers are now creating new models to make these predictions by combining the data to make better assessment of what regions of the world is more resilient to environmental changes or which ones would suffer serious consequences when these events happen. The combined data are beginning to reveal hotspots where the combination of the ever increasing population and changes in the climate will have the most significant impact on the people in the region, especially in the urban regions.

Researchers like Brian O'Neill at the National Center for Atmospheric Research are now working on a model that project the rate at which people move into areas in different countries This movement of people into an area is called urbanization, the start of a city. The world population is trending to rapid growth in the urban regions of the world where it is predicted that by 2050 about 70% of the world population would be living in urban zones. In 2010 half of the world population were living in these zones. The irony here is that most of these new urban zones are developing on coastlines around the world that are susceptible to flooding and other extreme weathers. Some are even developing in arid regions where it is predicted to become drier. Obviously, finding water and growing food will be some of the problems that a growing population will have to face in a dry region.

There is another model created by demographers Mark Montgomery and Deborah called GRUMP (the Global Rural-Urban Mapping Project) that uses data collected at the neighborhood by neighborhood level. The data are obtained from sources such as regional censuses and satellites. Satellites are useful for spotting urban regions by seeing the amount of light coming from regions at nighttime.