By: Bill Henderson
‘Alarmists’ like me argue that climate change is now an emergency.
A reasonable fear of what has come to be called ‘ dangerous climate change’ combined with the brutal logic of global carbon budget science after at least two wasted decades strongly suggests that only emergency action to limit emissions globally could prevent a humanity threatening catastrophe.
“So this is where we’re at: stuck between temperatures we can’t possibly accommodate and carbon reduction pathways we can’t possibly achieve.”
The rate of temperature increase due to anthropogenic warming (increasingly fed by latent positive feedbacks like melting permafrost) is another very under-appreciated possibility in the suite of climate change dangers. Consider this sketch of what we know about this rate of temperature increase problem below – are you an ‘alarmist’ too?
Here is part of a Science Daily ( Aug 31 2007) article on a key science paper:
There are a few studies that focus on the consequences of the rate of climate change. Most of these are ecological studies. They leave no doubt that the expected rate of change during this century will exceed the ability of many animals and plants to migrate or adapt. Leemans and Eickhout (2004) found that adaptive capacity decreases rapidly with an increasing rate of climate change. Their study finds that five percent of all ecosystems cannot adapt more quickly than 0.1 °C per decade over time.
Forests will be among the ecosystems to experience problems first because their ability to migrate to stay within the climate zone they are adapted to is limited. If the rate is 0.3 °C per decade, 15 percent of ecosystems will not be able to adapt. If the rate should exceed 0.4 °C per decade, all ecosystems will be quickly destroyed, opportunistic species will dominate, and the breakdown of biological material will lead to even greater emissions of CO2. This will in turn increase the rate of warming.
In a follow up paper on the same research Leemans and Van Vliet 2006 advise not exceeding a precautionary 1.5C and staying below a rate of less than 0.05C increase per decade.
But according to the World Meteorological Organization’s Annual Statement on the Status of the Global Climate, global mean temperature has increased since 1971 at an average estimated rate of 0.166°C per decade. (The Science Daily article states: “According to the Intergovernmental Panel on Climate Change (IPCC), the global average temperature today is increasing by 0.2 °C per decade” but there isdisagreement so we’ll go with the lower estimate to be cautious).
Furthermore 0.166C is the global average increase – many parts of the world, especially higher latitudes are warming far faster. I could not find any research quantifying the rate of change per decade for areas of northern Canada (Alaska, Siberia), in particular the boreal forest which has been changing from a carbon sink to a source of greenhouse gases, and Canada’s Arctic permafrost lands. Temperatures have been rising by 2C-5C in these regions. How fast is the rate of temperature change at higher latitudes and is it effecting species and ecosystems in line with the Leemans and Eickhout predictions?
Finally, and of deep concern, there are time lags between when greenhouse gases are produced by burning and when temperatures eventually rise, time lags which are normally averaged out at about 40 years. Fossil fuel use and subsequent emissions over the 2000 – 2010 decade were approximately twice as high as fossil fuel use and emissions from the decade of the 70s.
The carbon cycle is complex but doubling emissions could mean a rate of temperature increase double todays 0.166C around mid-century. What rate of temperature increase should then be expected in northern Canada (Alaska, Siberia) by mid-century?
“If the rate should exceed 0.4 °C per decade, all ecosystems will be quickly destroyed, opportunistic species will dominate, and the breakdown of biological material will lead to even greater emissions of CO2. This will in turn increase the rate of warming.”
The boreal forest and the methane presently stored in permafrost are potentially huge carbon bombs.
Could we have already emitted enough greenhouse gases in the last decade – could there be enough GHGs in the pipeline already – to lead to a fast temperature increase and a cascade of die off in at least vulnerable and very important high latitude ecosystems leading to some variety of runaway climate change?
Could death for everything we care about be already in the pipeline? Without our knowledge? With no public debate at all? A nightmare we will eventually wake up to?
Is there any question that we should act with needed precaution given the present science and especially given our culpability in burning fossil fuels? Isn’t this precaution the bottom line concerning what we owe future generations? This should mean not exceeding a precautionary 1.5C and staying below a rate of less than .05C increase per decade.
But, of course, those who do have the power in our society are too busy trying to keep the economy’s head above water to worry about catastrophe for humanity decades from now. Governments are quick to act proactively when they see the risk of contagion from the possible default of weakened peripheral economies but seem to have no planning at all to protect the health of far off ecosystems even though this accidental destruction threatens their societies far more.
Our business dominated leadership has never heard of Leemans and Eickhout and 0.4C per decade and could care less. In their opinion those concerned with the environment and future generations belong to left wing, pseudo-religious cults.
And even if there is a die off incident in boreal forests in Alaska, Siberia or Canada in the next decade, this ‘Pearl Harbor event’ would come too late.
I admit to being an ‘alarmist’. Isn’t there good reason for concern? How far do we have to go over planetary boundaries blinded by greed, ideology and ignorance before those who can initiate emergency action recognize the emergency?
About the author: Bill Henderson is a frequent contributor to Brave New World on Climate Change.