In 2007, The Intergovernmental Panel on Climate Change (IPCC) concluded that warming of the climate system is “unequivocal.” Climate change has already led to observable increases in global average air and ocean temperatures, widespread melting of snow and ice, and rising sea levels. Eleven of the last twelve years (1995-2006) rank among the twelve warmest years in the instrumental record of global surface temperature (since 1850). Our response to this crisis must take into consideration the predicament that those who have contributed the least to the problem stand to suffer the most from it.
Although the local effect of climate change is determined by geography, topography and other physical characteristics, the poorest nations, communities and individuals, who have the least capacity to respond, are likely to be hardest hit. Less developed countries will have the least capacity to cope with the devastating impacts of extreme weather events, rise in sea level, drought, disruption of water and food supplies, impacts on health, and the destruction of natural resources. As a result, the poor will not only be put at greatest risk by the physical impacts of natural disasters and climate change, they could also bear a disproportionately greater economic burden from any program to address it.
In the United States, climate related events and even modest emissions reductions could place a significant burden on the poor. For example, reducing greenhouse gas emissions by only 15 percent from 2005 levels will impose an estimated $750-$950 a year in added costs on the poorest fifth of the population.  Scientists have called for reductions of 80% in greenhouse gas emissions by 2050 to avoid the most severe effects of climate change. The financial burden of these reductions will undoubtedly increase with a more aggressive program.
Both here in the United States and abroad, the poor will suffer the most from climate change. For example, yields from rain-fed agriculture in sub-Saharan Africa could be reduced by up to 50% by 2020. Elsewhere, increased flooding will cause outbreaks of diseases such as malaria and cholera. Changes in precipitation patterns, subterranean aquifers, and the disappearance of glaciers will impact the entire biosphere, affecting water availability for human consumption, agriculture and energy generation globally and in the United States. Development NGOs estimate that it will cost upwards of $50 billion annually to adapt to these conditions.
The community relations field should at both the state and federal level: support measures to protect vulnerable populations (at home and abroad) from environmental damage related to climate change and that limit the economic burdens of new policies on those populations (including efforts to direct revenue generated by climate change legislation toward such programs); support increased funding for programs that help vulnerable populations pay for their immediate home energy needs and reduce their energy demands; support efforts to create new jobs and job-training programs to help those who lose their jobs as a result of new environmental regulations and policies; support studies that examine the effects of climate change on vulnerable populations and facilitate implementation of emergency plans to respond to these effects; promote multilateral international cooperation to deal with this issue.
 Center for Budget and Policy Priorities