Archive for the ‘Climate Change’ Category

Preston Manning on Climate Change

Monday, September 14th, 2009

There’s a great blog tracking the lead up to the Copenhagen conference on climate change from a Canadian perspective. Written by sustainability activists Rebecca McNeil and Darcy Higgins, it addresses the political and social issues, as well as the urgency of climate change.

Today’s post is about a speech Preston Manning gave to the Empire Club of Toronto on why we need to take action now on climate change.

Religion and Climate Change

Monday, September 7th, 2009

Back in May I wrote a piece called Why We Need More Churches about how religious communities provide social support and help in organizing for social and environmental justice. Now a former UK chief government scientist is making the same point, specifically with reference to climate change. I hope that religious communities across the world will pick up on his message.

Forget Shorter Showers

Monday, July 27th, 2009

So you recycle, you turn the lights off when you leave the room, you compost, you don’t idle your car and you take shorter showers. If everyone follows your example, would that fix the environmental problems of the world? Derrick Jensen’s essay makes a convincing case that without political and legal change, personal change means little.

Where Does Energy Come From?

Wednesday, July 22nd, 2009

As the wisdom of burning fossil fuels fall further into doubt and many grope for a replacement source of energy, it recently occurred to me that a good question is “Where does our energy come from?”

No, really. It might seem like the answer is very complicated, but at some level it’s simple: sunshine. That’s actually an almost complete answer.

“What about hydro electricity”, you might ask, “doesn’t that come from falling water?” Yes, it does, but, to paraphrase Newton “what comes down must have gone up.” And what lifted the water, so that it could fall through the generator? The sunshine, which evaporated the water, lifting it into the air. As we look at other sources of energy, we come to the same conclusion. Oil, natural gas and coal are organic matter millions of years old. The energy in that organic matter is stored sunshine, captured by algae via photosynthesis. Windmills are turned by gusts that happen when sunshine warms the earth, in turn warming the air above it and causing that air to rise, creating air currents. Burning wood or other organics is liberating sunshine that was stored much more recently than that in fossil fuels.

There is an exception to the rule. Nuclear reactions also contribute to our energy supply. Nuclear fission reactors use radioactive elements created in the hearts of stars billions of years ago. Geo-thermal energy uses the heat released by natural nuclear decay inside the Earth.

What can we say about these sources? Well, nuclear fission energy relies on radioactive isotopes. These are found in the Earth’s crust and mantle in small amounts. We can only extract them from a certain depth, because it’s too hot if we dig farther. There is a limited supply within the crust, and there are different estimates of how long that supply will last, as well as how much energy we can get out, but the supply is certainly limited.

Sunshine has a similar limit. Quite a bit of it falls on the earth, but capturing it efficiently is difficult, so we are only able to obtain a very small percentage of the energy that reaches our planet. Most of the sunshine powers other processes that are useful to us, such as plants and animals in the biosphere, our own agriculture, the wind and rain, melting snow in the spring, making objects visible, etc. We wouldn’t want to use most of the sunshine to create energy even if we could.

It’s important to remember these limitations as we talk about alternative energy. Nothing produces limitless energy, so our planning for the future and our actions for today need to take into account the limits that we’re up against.

Green Products

Sunday, July 5th, 2009

Rex Weyler has an excellent article discussing green products and why we need to be better informed about their ecological effects. He also explains the concepts of overshoot and how our technophilia is preventing us from adequately addressing overshoot.