The most basic assumption driving this site is that population growth and corporate economic growth team with per capita resource consumption as the primary drivers of today’s ecological decline. Perhaps, then, it’s best to devote this early entry to a bit of support for that assertion. There are people, after all, who question it.
Let’s start with population growth. Especially prominent among those who dismiss the idea that population growth is a problem have been a few economists—most notably the late Julian Simon—who cheerlead population growth, arguing that it is always to our benefit. Natural scientists, for the most part, do not much question it as a major cause of environmental degradation. That in itself speaks volumes. Nevertheless, is it possible to use simple logic to demonstrate a link between population growth and environmental damage? I believe so.
More people, more warming
Consider climate change. There is now an overwhelming scientific consensus that human activity is contributing significantly to global warming. The implicated human activity is anything we do which causes greenhouse gas emissions. One of those things is driving cars which burn fossil fuels. Clearly then, everything else being equal, more cars means more anthropogenic greenhouse gas emissions — the primary gas of concern being CO2.
World population has doubled since the early 1960s. As a result of that doubling there are now far more cars operating than there were 40 years ago. There are, therefore, more auto-related emissions. Those increased auto emissions mean more CO2 emissions and more forcing of climate change.   It is therefore indisputable that population growth has contributed significantly to climate change. 
There, that was easy enough. And we could construct similar analyses of the relationship between population growth and other human sources of greenhouse gases. We could just as easily demonstrate the links between population growth and other aspects of environmental degradation. For a fuller discussion of the population-climate change link, see the relevant page on the Union of Concerned Scientists site. For more on the general topic of population and the environment try Al Bartlett’s excellent article, Reflections on Sustainability, Population Growth, and the Environment – Revisited. In future entries I’ll try to provide equally simple arguments to support other aspects of this site’s basic assumptions.
 Note that CO2, the most significant greenhouse gas produced by human activity, has not historically been regulated by auto emissions standards.
 For voluminous information on the relationships between greenhouse gases and climate change see the various documents at the IPCC website. Of particular relevance to this post, see the top graph here, illustrating the increase over time of atmospheric CO2 and the associated estimated radiative forcing.
 Just to add some perspective, the U.S. Department of Energy reports, in fact, that, “In 2003, the transportation sector accounted for about 27 percent of total U.S. GHG emissions, up from 24.8 percent in 1990.” (Thanks to Wacki, who maintains the LogicalScience.com climate change blog, for that reference.)
Image source: Stephen Codrington, posted on Wikimedia Commons under a Creative Commons Attribution 2.5 license