Archive for Climate change

Noise in the signal

It’s just possible that you’ve heard the UK is unusually cold right now. We’re recording near-record low temperatures night after night, everyone’s stopped working/going to school, and of course we’ve run out of salt and grit for the roads.

And of course people have started to question how we can possibly have such cold weather when the planet is supposed to be getting hotter. One commentator even went so far as to suggest that blind faith in global warming led to councils not having enough grit stockpiled to keep the roads clear.

It doesn’t take much to understand the concept that there is a difference between the climate, which is the underlying trend, and the weather, which is the chaotic seasonal fluctuations around that trend, but for some it’s asking too much. Read the rest of this entry »

Ruin is the destination toward which all men rush

To understand how individuals interact biologists use a branch of mathematics known as game theory, the central assumption of which is that entities (usually individuals) behave rationally; that is, they act in their own best interests in light of the available information about what others are doing. From an evolutionary perspective, it’s about maximizing one’s own success relative to that of others.

A famous example of the application of game theory to behaviour is the so-called Prisoner’s Dilemma. Imagine two suspects, held in separate cells. If they both stick with their story (loosely, “I dahn’t nah nuffin’ mate”) the authorities will have no evidence on which to convict and both will go free. Read the rest of this entry »

Oh no we don’t!

The pantomime season is approaching fast, and seemingly kicked off with this piece on the BBC’s Countryfile programme last Sunday, in which Tom Heap explored the intriguing question of “why burning trees is better for the environment than many think”.

Subsequent media coverage has quoted the support of a number of conservation bodies, including ourselves, for the Forestry Commission’s desire to harvest two million tonnes of woodfuel a year from the UK’s “undermanaged” woods. Our supporters would rightly question why a woodland conservation charity like the Woodland Trust would wish to see trees felled and burned to produce heat. Read the rest of this entry »

Is it trendy to deny climate change?

I don't believe it! Victor Meldrew.

Just about any online conversation on climate change, such as today’s story in the Independent that we’re staring at a six degree rise by 2100, rapidly descends into a mud slinging match over the cause of climate change (just look at the comments following the main piece).

In fairness, there probably aren’t that many people out there that deny climate change is really happening. The few high-profile individuals that do are seen by most as the frontsmen of the climate equivalent to the Flat Earth Society: the serious debate isn’t around whether climate change is happening, but what’s causing it. Read the rest of this entry »

Africa sinks up

Tree measurements show that African rainforests are locking up carbon faster than ever

Tree measurements show that African rainforests are locking up carbon faster than ever

While much of the alarm over global deforestation centres on the Amazon rainforest, which continues at a shocking rate, African rainforests receive relatively little attention. Yet a study published today in Nature demonstrates the increasing size of the carbon sink these forests contain: similar to Amazonian forests in per unit area terms.

A large international team of scientists, headed up by Simon Lewis at the University of Leeds, found that across 79 plots in ten African countries, the above-ground carbon storage increased by 0.63 Mg C per hectare per year, between 1968 and 2007. Scaling up to include unmeasured material — roots, small trees, rotting trees and so on — brings the continental increase in carbon storage to 0.34 Pg C (that’s 340 million tonnes of carbon) per year. Read the rest of this entry »

A good place to bury bad news

Lovelock proposes the world's biggest barbecue

Lovelock proposes the world's biggest barbecue. Photo (c) Peter Guess

Carbon sequestration — taking CO2 out of the atmosphere, as opposed to merely not adding to it — is the thing that will fix the mess we’ve created. Avoiding emissions is all well and good, and will ensure that things get back to how they should be, eventually. But wouldn’t it be a good idea to help things along a little?

There have been lots of suggestions about how we might be able to draw CO2 back out of the sky. Solutions range from the mechanical (e.g. the fabled carbon capture and storage beloved of coal-firing power companies), through the chemical (like iron enrichment of the oceans to promote blooming of carbon-storing algae) to the biological (such as our favourite, planting trees). Read the rest of this entry »

Died in the USA

Climate change isn't just affecting the oldest trees

Trees throughout the forest age structure are affected by regional warming and drought stress. Photo © Jerry Franklin

Old growth forest on the western United States is dying back at an increasing rate, accoring to a study published this week in Science magazine. The study, led by USGS biologist Phil van Mantgem, found that background mortality rates — those not directly attributable to some catastrophic effect, such as fire — have risen rapidly in recent decades.

The study, which used census data from 67 long-term plots located in ancient forests (average age 450 years, some sites in excess of 1000 years), found that mortality rates had increased at the vast majority of sites, whereas recruitment rates — replacement of dead trees with new ones — had neither increased or decreased over the same period.

The dieback couldn’t be pinned down to any local effects, such as pollution, local competition or fire prevention measures. Instead, say the study’s authors, regional warming and the ensuing water problems it brings — faster snowmelt leading to longer summer drought — are putting the strain on the trees. Read the rest of this entry »