global warming - why even doubters should pay attention

Whether or not you believe that humans are the cause of climate change, it's hard to deny the accumulated studies suggesting that the earth's atmosphere is warming. Many will still argue that it doesn't matter: the climate goes through cycles, so what's a few degrees up or down?

An article published online yesterday in Nature provides a statistical analysis of literally thousands of observations of natural systems from around the world, taken between 1970 and 2004.

Among the warming-linked changes seen in the study are the timing of plant flowering, bird nesting, ice melting, salmon migration and pollen release; declines in populations of polar bears, krill and penguins; and increased growth of Siberian pines and cool-water ocean plankton.

There seems to be a clear picture forming of significant change in biological systems. Again, does it really matter if a few species go extinct or fruit ripens earlier or later? In some respects, we don't know how much it matters, but that in itself is reason to be cautious. Business as usual is to deplete the earth's resources - both the living and the stored - so arguments that "there is no proof of anthropogenic climate change, so we should just do nothing" are fallacious. We aren't doing nothing now; we are actively changing the environment in which we live. If we clear the oceans of fish, what does that do to the rest of the food chain? Biodiversity is important for a number of reasons, and one is to provide ecological resilience. It's easy to forget that we are part of the chain, and while we may be able to overcome some obstacles, we are not immune to the laws of nature. Some species have gone extinct in dramatic fashion, not gradually. You have been warned.

So here's my short list of why a few degrees matters, and why we need to do something about it.

1. Availability of unpolluted, drinkable water is a serious challenge, and increased temperatures will increase evaporation of scarce inland supplies. I am not talking only of evaporation from dams used to supply drinking water. There are swimming pools that need to be topped up, and agricultural dams. Agriculture is responsible for 70% of water use worldwide, and we are already draining nonrenewable 'fossil water' supplies. The apparent solution is desalination, but that would require huge amounts of energy: twice the current global electricity production, by one estimate.
2. Increased air temperature affects ocean temperatures, with impacts on storm development, sea life, water currents, water vapour and precipitation. This can affect the distribution of available freshwater supplies, and models are indicating noticeable changes with relatively minor changes in average regional temperatures. This will impact agriculture and drinking water.
3. Changes in temperature and humidity will change habitats for insects, and the number of people exposed to diseases like malaria.
4. If lifestyles, building designs and technologies don't change significantly, then increased temperatures will increase the use of air conditioning, which is a significant user of electricity. Aside from the effect of greenhouse gas on climate, the emissions from fossil fuel burning pose a serious health risk. And nuclear is not a long-term solution: by some estimates, there is only a 15-year supply of uranium left.
5. Agriculture will change not only because of water shortages, but also because of habitat migration. This is already affecting crops from Rooibos in South Africa to grapes in France.
6. Migrating birds are getting confused, and changing their habits. This makes them vulnerable. Species have adapted to climate change over millions of years in the past, but never has change taken place at its current pace, without serious ecological repurcussions. As I've already mentioned, the ecosystem is an integrated system - impacts on one species can have unpredictable results for others. And here's a case where we are directly affected: declining bee populations in the US, widely reported last year, has an undeniable impact on a number of crops that we rely on for food.
7. A change in global average temperature of 5 degrees Celsius is the difference between our present climate and that of an ice age. A few degrees is dramatic.
8. Finally, you can forget everything I've written here, and one fact remains. Popular opinion is now aligned with climate science, and as environmental concerns become increasingly politicised, business decision-making will be forced to treat the anticipation of long-term climate change as a factor to consider now. Emission abatement policy will create an ever-tightening noose to force transformation, until we see that climate change has been slowed or reversed. And we won't be seeing that anytime soon.

Climate science is not conclusive in every respect, and probably never will be. Nobody has "proved" the causes and effects global warming, but that's not what science does.

A colleague of mine has paraphrased physicist and Nobel winner Richard Feynman in saying that the essence of religion is faith, and the essence of science is doubt. Doubt, the willingness to question, the willingness to learn more, the willingness to set aside theories that do not end up being supported by experience are all critical to solving the problems of our time. Climate theories will develop and change, but what they are telling us now is that we need to act now. And the body of evidence suggests, beyond reasonable doubt, that if we don't act we face the possibility of irreparable and unpredictable damage to the ecosystem, the economy and social systems.

Comments

[Audrey]

Hello Rory

Did you see the thing on grist about Tiggers when they can’t climb downwards ‘cos their tails get in the way? :-)

I don’t know what’s going on with the comments over at the new recycle bog, but I could have sworn I saw a comment from you there, before it disappeared into thin air. I’ve no idea what it said, the comment, ‘cos I just saw “Rory Williams” and I clicked “yes go ahead and publish already you silly blog don’t you know Rory’s one of the good guys???”

So, this is just to say, thanks for the nod, even though it’s gone off somewhere into the vastness of the binary universe. I hope it has fun out there, and manages to go where no-one’s gone before, and brings back an account of its adventures.