Scientific discussions of climate change often center on numbers: average temperature increases or decreases to be expected, alterations in rainfall amounts, adjustments to the growing season, and the like. It is easy to lose sight of the fact that we are ultimately interested in climate change because it has the potential to alter the livability of regions and, perhaps, the planet itself. This module steps away from those numbers, the questions of how much climate change might occur, and takes a look at the question of what if. It shows how life forms plant and animalmight be affected by changes in various aspects of climate. We look at some of the possible biological consequences of the familiar physical aspects of climate change (temperature, rainfall, ultraviolet radiation, etc.). We also explore what we call changes in the chemical climate, alterations in the chemical composition of the atmosphere that could be substantial enough to elicit responses in biological organisms.
Uncertainties are plentiful in any discussion of biological consequences of
climate change, perhaps even more than in other facets of the climate change
debate. But that should not deter us from considering the range of possibilities.
It is precisely the abundance of uncertainties that makes this one of the most
exciting and crucial areas of global change research.
Scientists can be sure that every new finding will receive both intense interest and intense scrutiny. This creates a challenge for the scientists and a dilemma for policy makers, who must chart a course for their countries despite the uncertainties. We each must decide how much of a climate change insurance policy we will pay for in the face of many unknowns. I hope that this module will help you to answer that question for yourself.