Russian Roulette

“Put starkly, current emissions pathways risk playing Russian roulette with the world’s largest forest. We can’t just wait and see because there is no going back. We won’t know we have passed the point where the Amazon turns from a sink to a source until afterwards, when it will be too late.”

Simon Lewis, 2011

I came across this quote while browsing the excellent blog http://www.redd-monitor.org/ which tracks REDD+ in the news. It raises the worrying point that with rising global temperatures a climate “tipping point” will be reached when forests will switch from being a CO₂ sink to become a CO₂ source. This is described by Phillips et al (2008) who used long-term forest plots to monitor changes in tree growth. They found that forest dynamics (growth rate, recruitment rate, death rate etc) have accelerated through the 80s and 90s, most likely driven by increased atmospheric CO_2. They highlight the Amazon’s sensitivity to atmospheric changes and warn that in the future temperature increases will increase photorespiration and tree mortality which both release carbon into the atmosphere. There may also be compositional shifts towards faster-growing species which tend to have lower wood density and therefore contain less carbon.

 Graphic from Lewis et al 2011 showing the extent of the 2005 and 2010 Amazon droughts

These changes may already be happening. The Amazon experienced two severe droughts in 2005 and 2010 (illustrated above) which caused widespread tree mortality and carbon losses. Droughts also increase the risk of forest fires. The 2005 and 2010 droughts have been linked to anomalous elevated sea surface temperatures (SSTs) in the North Atlantic (Lewis et al 2011) and under future warming scenarios such droughts are predicted to become more frequent. Elsewhere, a short study by Lindroth et al (1998) observed Swedish boreal forest acting as a net source of CO₂. Worrying indeed.

This potential transition from forest friend to forest foe brings me to another excellent blog, The Global Mirror, written by Cathy Granneman, and in particular her recent post on forest albedo. To put it bluntly reading it made me feel slightly how I felt when I finished reading And Then There Were None or The Hollow Man for that matter: mind = blown. To summarise, forests are generally dark and have lower albedo than other biomes which mean they reflect less insolation. This warming effect, although compensated to some extent by evaporative cooling, has the potential to offset any benefits from carbon sequestration, particularly in boreal regions. Research by Gibbard et al (2005) simulated global land cover change with unconstrained SSTs and found that if all current vegetation across the globe was replaced by trees there would be a global mean warming of 1.6°C! This is clearly an unrealistic scenario but highlights that a lot more research is required before blindly relying on forest carbon storage to mitigate global warming.

It is undoubtedly a tricky one. Unlike in a detective novel we can’t flick to the end and see how it all works out. The future is far from certain but we should use the evidence available to us and try our damned hardest not to get shot in the head.

The mother of all threats

Barack Obama is safely installed back at the helm of the world’s largest global economy just days after Hurricane Sandy brutally forced the issue of climate change back into the limelight. There have since been rumblings of hope that now may be the time for the USA to tackle this “mother of all threats” and Al Gore, a renowned climate champion, has called for Obama to introduce a carbon tax.

This raises the question, that if something should be done, who should be doing it? Following a recent comment I wanted to elaborate a little further about where the burden of responsibility lies, and to what extent the REDD+ approach is really equitable.

Flooded streets under Manhattan Bridge in Brooklyn illustrate New York’s growing vulnerability to destructive storm surges. B. MATTHEWS/AP

http://www.nature.com/news/hurricane-sweeps-us-into-climate-adaptation-debate-1.11753

For starters REDD+ schemes by their very nature involve developed countries instructing developing countries on how to best manage their natural resources. This is slightly ironic really given that we have guzzled, burnt and flattened our own landscapes throughout the course of history. This aside, is it really ethical for the people with the cash to carry on, business as usual, and expect those living in some of the world’s poorest regions to change their livelihoods and restrict development in order to solve a problem that wasn’t even caused by them in the first place?

In a word, no. But the reality is that the forests with the greatest potential for carbon sequestration are in the tropics (see my previous post) and so if we want to save these forests and their troves of carbon then it is essential to engage with the people living in these regions. However, it is vital that developed countries also make meaningful changes and cut domestic CO₂ emissions. Worryingly, there is a danger that REDD+ schemes may reduce incentives for such action.

To avoid this Maslin and Scott advocate “robust ceilings on the use of REDD+ credits in domestic carbon markets”. In other words there should be a limit on how many carbon credits can be used to meet emissions targets.  They also emphasise the importance of “shared responsibility”. We are all in this together, as the image above illustrates all too well.

Norway – a case study

I love Norway. All those beautiful fjords, a fantastic welfare state and world leaders in the renewable energy industry (99% of mainland electricity is generated from hydropower plants). They have also just announced they are doubling the carbon tax on the North Sea oil industry (http://www.guardian.co.uk/environment/2012/oct/11/norway-carbon-tax-oil). The funds generated from this will be used to establish a fund to tackle the impacts of climate change in developing countries and also combat deforestation.

Sognefjord, Norway. What’s not to love?

Norway was also one of the first countries to initiate a REDD scheme with the “groundbreaking” Oslo Pact formalised in May 2011. This deal between Norway and Indonesia could see Indonesia (the world’s 3^rd largest emitter of greenhouse gases) earn up to $1billion for forest conservation and reduction of deforestation. The crux of the pact is a 2-year suspension of new logging permits for carbon-rich peatlands and old-growth forests. The funds from this scheme will be used to develop infrastructure to monitor and protect forests, and reduce illegal logging.

However, some people are more cynical about this “landmark” agreement. Clements et al (2010) explain their reasons for “cautious optimism”. For a start Indonesia has a poor history of sticking to conservation commitments. A pledge to ban expansion of oil-palm plantations on peatlands in 2007 was scrapped just 2 years later, allowing an area of 2 million hectares (equivalent to 2 million rugby pitches) to be cleared. A similar plan to reduce the number of forest fires also failed. Furthermore money in Indonesia’s Reforestation Fund has, more often the not, been spent on projects unrelated to reforestation. Finally this pact only applies to “new” permits, and land already destined for conversion to plantations will not be protected.

Edwards et al (2012) also have reservations, particularly the fact that the area of forest protected under the scheme is tiny in comparison with the area that can continue to be exploited. The moratorium specifically applies to “old-growth” forest, excluding a much larger area of selectively-logged forest which may have high biodiversity and carbon stocks. A large portion of the protected “old-growth” forest is in mountainous areas and unlikely to be under threat, potentially violating the requirement of “additionality” for REDD to be effective.

So is it all a waste of time? I don’t think so. There are clearly lessons to be learned but the Norwegian-Indonesian partnership is undoubtedly a step in the right direction. It is now time for other nations to follow Norway’s lead.