It may already be too late to head off major famines in the mid-part of this century. That's one of the clear implications of two shocking new reports, by PriceWaterhouseCoopers and the World Bank.
Two degrees of global warming may not sound much to most people – but combined with extreme weather events – it is the point at which the world's food supply, and grain production in particular, face serious jeopardy. And if grain runs short, the first thing to go is meat. So this isn't just an issue that will hit the poor and the already hungry: it will affect everyone who eats.
The "Too late for two degrees?" report by PWC, one of the world's largest accounting firms, is blunt: "Now one thing is clear: businesses, governments and communities across the world need to plan for a warming world – not just 2ºC, but 4ºC and, at our current rates, 6ºC."
"This isn't about shock tactics, it's simple maths," PWC partner Leo Johnson told Canadian science writer Steve Leahy. The 'simple maths' says the world has been cutting its carbon emissions at only one sixth of the rate needed to avoid 4-6 degrees of global warming. In perspective: the US would have to eliminate all its existing coal-fired power stations in 8 years to meet its share of the 2 degree target – and much the same applies to Australia.
Its sobering assessment is echoed by a second major report, by the World Bank, which warned that places like India could lose up to half their grain crops under two degrees of warming, and Africa a third of its arable area. It links 13 of the most devastating weather events of this decade to man-made global warming.
The reports landed just before the United Nations Climate Change conference in Doha (Nov 26-Dec7), already shaping as another of those dispiriting affairs where pious sentiments, platitudes and good intentions substitute for concrete, decisive action by what is already rated as the least-effective worldwide political leadership in a century.
However the real significance of these reports is that we are now looking down the barrel at climate-induced economic shocks that will make the GFC look like a hiccup.
What some of those shocks might look like will be discussed by scientists attending the
Second Australian Earth System Outlook Conference hosted by the Australian Academy of Science in Canberra. They explore some of the 'tipping points' where key systems break down and shift to a new, more perilous, state. The focus is on the continuing disconnect between climate science and society over carbon, impacts on the poles, the oceans, the Great Barrier Reef, and food security.
Food security is vital because that's the main way most people will personally experience climate change – as huge, unexpected hikes in the cost of foods they had previously taken for granted, due to drought, flood, tempest or searing temperatures. So far, it appears the world has lost around 4-6 per cent of its major grain harvests due to global warming.
What is not generally understood however is that global (and Australian) food security also depends on a series of scarce resources that are becoming increasingly unaffordable to farmers: land, water, oil, fertiliser, fish, finance and technology, to name a few. Climate change is now amplifying these emerging scarcities in unpredictable ways.
For example, it is probable that key regions of the world will run out of water in the next 10-20 years – the north China foodbowl, the Indo-Gangetic plain, the US Midwest, and the Middle East. These could trigger mass migration by tens of millions of people as well as the outbreak of local conflicts, as numerous military studies now attest. Climate change, with its sudden, unanticipated impacts, will exacerbate water scarcity and flood destruction of food systems.