a consequence of the cumulative emission of carbon dioxide (a by-product
of fossil fuel use) and other chemicals over the past two centuries, the concentration of these
gases in the global atmosphere is growing dramatically. These chemicals capture more solar
energy within the atmosphere, and hence average global temperatures are rising – by about a full
degree Celsius (on land) over the past half-century. The rise in global temperatures is causing
many serious consequences, including changes in rainfall, rising sea levels, extreme weather and
storms, and changes in plant and animal habitats.