Not Just for Tree Huggers

Citizen’s Guides to Climate Change: How to Sort it All Out without Getting a PhD

This posting is the third in a series on how you can figure out what’s going on with climate change, without having to get a PhD in climatology and without going crazy from the conflicting messages in the media. My first post showed how you can bypass the media confusion by finding out what real scientists are saying. My second one showed how strongly scientists agree on the basic facts: Earth is warming. We’re causing it. The biggest contribution is burning fossil fuels, which accumulates heat-trapping gases such as carbon dioxide in the atmosphere. We need to burn less fossil fuel to keep the effects from getting too extreme.

In this post, I’d like to acquaint you with some of the people besides scientists who are concerned about climate change. Some of them may surprise you. Who they are and what issues they identify may give you a sense for why mitigating climate change is important for all of us.

It is no surprise that environmentalists call for climate action. If we continue increasing fossil fuel consumption, people who are small children today could experience, within their lifetimes, an increase in earth’s average surface temperature of 2 to 5 ºC (4 to 9 ºF), which is nearly as great as that between the last Ice Age and today. That rapid change would disrupt ecosystems all over the world. As warming exceeds 4 ºC, there is a risk of major extinctions, involving 40 to 70 % of the plants and animals assessed in the 2007 report of the Intergovernmental Panel on Climate Change. We can preserve much more of the natural world if we burn less fossil fuel and limit the warming to 2 ºC or so. Because extinct species are gone forever, the decisions we make over the next few decades will determine how much poorer a world we leave to every human generation that comes after us.

What you might not have guessed is that the American Academy of Pediatrics, American Medical Association, World Health Organization and other groups concerned with human health are also calling for action to minimize global warming and prepare healthcare systems to cope with it. These groups point out that climate change can affect people’s health in a variety of ways, including extreme heat and drought that hurt agriculture and increase malnutrition; injury and disease from more severe floods and hurricanes; water pollution due to flooding and drought; higher temperatures that worsen the chemistry of air pollution; and expanded ranges of pests that spread disease.

Another group taking climate change very seriously is the American military. Recent reports from the US Department of Defense and intelligence agencies have looked at climate change as a concrete threat to national security. Global warming brings more drought to places already too dry, more flooding to places already plagued by floods, and less food and water to people who already have too little, especially in parts of Africa, South Asia, the Middle East and the Caribbean where social tensions are high, governments are weak and resources for coping with disaster are lacking. In such places, the added climate stresses may exacerbate existing risks of violence and political instability. As the military describe it, global warming is a threat multiplier.

We have already seen violence exacerbated by the kinds of environmental stresses that climate change will increase. The genocide in Darfur, for example, may have happened in part because expanding deserts forced herders into land occupied by farmers with different tribal, ethnic and religious identities. Violence has also occurred in India between natives and migrants forced out of Bangladesh by flooding and rising sea levels. As global temperatures rise, the environmental stresses and the resulting conflicts will continue to increase.

Although the military have focused on climate change as a destabilizing force in poor countries, it is a very real problem for richer ones as well. The US Department of Agriculture has been looking at how global warming might affect food production in the United States. The effects they describe are complicated, difficult to project, and likely to vary by crop and by region. However, some of the most recent analyses indicate that, if fossil fuel burning increases as it could well do, corn and soybean yields in the US could fall by as much as 60 to 80% by the end of this century. The losses will be much less if we minimize the global temperature change by burning less fossil fuel.

As these crop-yield projections illustrate, radically changing the climate can have real economic consequences that are potentially serious but hard to predict. One group that knows about dealing with uncertain risks of economic loss is the insurance industry. Many leading insurers, noting the ongoing increase in the number and severity of weather disasters, have called for action to minimize climate change. Another leader in insurance, Lloyd’s of London, has looked at climate change from a broader business perspective. They start with the overwhelming scientific evidence for human-caused climate change. They then identify a number of consequences that could affect businesses worldwide:

  • Water scarcity
  • Food production not meeting demand
  • Risks of mass migration from poor to rich countries
  • Risks of increased international conflict and insecurity
  • The increased unpredictability of a warmer world

The American Academy of Pediatrics, the Departments of Defense and Agriculture, and Lloyd’s of London are looking at climate change not as environmentalists, but because it is their job to assess risks and plan for them. Looking at the same science from somewhat different points of view, they each find that global warming presents significant challenges for our society.

A common thread in their analyses is that climate change can affect our lives in complex ways, with potentially big, but imperfectly known consequences. Climate change is about making choices in the face of imperfect information. Doctors, generals and insurance companies do that all the time. What we know for certain is that we have a real problem, and that the risks will increase as global temperatures rise. Our choice is how much risk we want to tolerate, and how quickly we are willing to reduce our consumption of fossil fuels. The more quickly we do that, the richer and more secure will be our world and the one we leave to our children.

Creative Commons License This material by William F. Avrin is used here by permission of the author, and is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.


About Bill Avrin

As a physicist, but not a climatologist, Bill Avrin has spent nearly twenty years looking at how citizens who aren't climate scientists can understand what science is telling us about climate change. Bill has written and spoken on climate change for PV Magazine, Vision Magazine, the website Understanding Climate Change, California State University, Fresno, the Salk Institute's Art and Science Forum, and numerous civic groups.


  1. Angela says:

    Very interesting article. I think a lot of people fail to realize that the military considers climate change to be such a threat. Thanks for highlighting that and the fact that the insurance industry is very concerned about it too.

  2. Excellent site. Plenty of helpful info here. I’m sending it to several buddies ans also sharing in delicious.
    And of course, thank you in your effort!

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