Sunday, June 09, 2013

Summer is icumen in ...

On Tuesday this past week I spent some time with a work colleague at Penrith telephone exchange.

Ironically it was an absolutely beautiful warm day with hours of bright sunshine but one of the things we were doing was searching through the data for weather in the UK this year to date, trying to establish if there was a correlation with the cold weather we have been having, trying to establish if the fact that on some measures Britain had the coldest spring for fifty years had produced an impact on the number of issues with BT's network.

Today is the sixth consecutive glorious day since then, and I am finally coming round to the view that we may actually get a summer this year.

More astute supporters of the view that government need to take action about the environment have long since stopped talking about "Global Warming" and started talking about "Climate Change" instead - firstly because the potential harmful impacts on the environment which we need to avoid are far wider than just temperature, and secondly because the data on temperature, though it does suggest that some degree of warming may be taking place, as far more complex that the simple story of runaway temperature increases that the most alarmist narratives used to give.

An example of a worldwide environmental problem which is nothing to do with temperature is the slow but steady acidification of the oceans over the past few decades, which if it continues much further will being to have catastrophic consequences for fisheries and communities dependent on them: an example of a potentially serious national environmental problem is the decline in bee populations. (Bees pollinate a lot of our crops.)

Ironically, one of the strongest pieces of evidence for climate change is something which has not happened, namely the big freeze that was once expected to have happened by now.

Historical records and the patterns found in the rings of trees suggest that the world had up until now had a series of temperature cycles lasting several hundred years which alternated between so called "little ice ages" and warm periods. The last "little ice age" lasted from tudor times to the Regency, and the history books tell us that the Thames froze completely over in at least 24 years over those centuries, providing opportunities for "Frost fairs" on the ice. In the year of the last of these, 1814, the Thames was frozen over with the ice sufficiently thick to take the weight of an Elephant which was led over the river just below Blackfriars Bridge.

The mid to late 20th century was supposed to be a warm epoch, and scientists and climatologists expected the temperature to drop sharply again at around the turn of the millenium. I can recall the cover of a "New Scientist" issue in my youth - it would have been some thirty or forty years ago - which showed an image of an icebreaker at work in ths English Channel near the White Cliffs of Dover, with a caption suggesting that such a thing might be seen before the end of the 20th century.

And of course, it wasn't. Temperatures in UK over the 21st century to date have been consistently higher than they were in the last half of the 20th century, although they have not, over the past five years, shown a clear upward trend of futher rises. Climate change experts have revised downwards their forecasts of the rate at which they think global temperatures will increase.

There may be those who see this as evidence to support the view that man-made climate change is a myth. The doom mongers who predicted a big freeze were wrong, they would argue, and the doom-mongers who are predicting warming are wrong now.

That would be a mistake. People who are tempted to look at the evidence in that way should be very careful to avoid clutching at any straws which might give them an excuse to avoid messages they don't want to hear.

There will be others who take the lesson from the fact that scientists have amended their views in the face of fresh evidence, that the earth's climate is far more complex than any of us, even the best informed scientists, understand. That means we would be wise to listen to all reasonable points of view rather than damn those who say something which challenges the current consensus as heretics or, God help us, "Climate change deniers." This time I agree

But that is not an argument for ignoring the environment. If the earth's biosphere and climate are more complicated than we understand, that is all the more reason to be careful about what we release into our ecosystem. "Doctor Who" is fiction, "The Day after Tomorrow" is ridiculous fiction, but the fact that there have been changes greater than we can imagine in our earth's environment, and that we do not fully understand what might trigger them to happen again, or spark off entirely new types of change, is no more than the truth. And under the precautionary principle, it is a reason to watch out for what imact we may be having on our world.

3 comments:

Jim said...

Having spent Friday and yesterday, lifting then re-laying a patio at Carlisle (2x12 hour shifts, shovelling sand and cement into a mixer, pushing it to the back garden (south facing) in a wheel barrow, then laying patio flags. followed by laying 3 tonnes of blue slate chippings, I can definitely confirm, both days were bl**dy hot!!!!!

Chris Whiteside said...

Too right - apparently Friday was the hottest day of 2013 to date!

Chris Whiteside said...

Apparently it will get cooler later this week, but the meteorology guys do think we are now going to have a summer ...