Wednesday, June 13, 2012

I will show you fear in a handful of dust

Groundwater depletion. A new study has calculated that the biggest single contributor to sea level rise over the last fifty years has not been melting ice from Greenland or Antarctica, nor melting glaciers, nor even the expansion of the oceans as they warm, but groundwater depletion. This helps to plug a previously puzzling hole between the observed rate of sea level rise over recent decades and estimated contributions from these other sources. Of course, there is an even bigger problem in many places that results from taking groundwater at a rate faster than it is replenished: running out. For three decades, Saudi Arabia used to export wheat grown in its deserts with water extracted from fossil aquifers (i.e. groundwater that fell as rain thousands of years ago and unlikely to be replaced anytime soon). In the last few years, its wheat production has collapsed and is expected to cease entirely by 2016. As a result, it is buying up productive land in Africa, which results in various other problems: dispossession of traditional owners (who may lack adequate documentation of land ownership), corruption of government officials involved in a lucrative business, reduction of local food stability and so on.

Economic collapse? An update to the 1972 Club of Rome study done by researchers at MIT predicts global economic collapse by 2030 on our present unsustainable trajectory. Much discussed, debated and derided at the time, the computer predictions of the 1972 publication The Limits to Growth, have been tracking well with historical data over the last few decades and their timeframe of very serious ecological and resource problems by 2030 do not need to be substantially revised, according to the new study.

Australian droughts and floods: A land of (more extreme) droughts and flooding rains? This is an excellent intro to the hydrological effects of climate change on Australia and is the first in a recent series on hydrological changes in Australia. Parts Part Two, Three and Four.

Biodiversity decline: EU farmland bird numbers have dropped by 50% over the last thirty years, largely due to farming policies.

2011 CO2 emissions update: John Cook outlines IPCC and IEA scenarios for different emissions trajectories we could follow. Note that the very best (and most difficult) ones still involve major disruption and difficulty in a harsher and less predictable world. They are also likely out of reach without radical and rapid shifts in the global political and economic climate.

UK Climate Policy: George Monbiot traces the latest watering down of UK climate legislation. The UK's Climate Climate Act passed in 2008 with very close to unanimous support, making it the first piece of national legislation setting targets for greenhouse gas emissions reductions in the world. When originally introduced in late 2007, the bill called for a 60% reduction by 2050, but this was increased to 80% on the urging of NGOs, church groups and a Royal Commission.

Great Barrier Reef: The UN has warned that the reef's World Heritage status will be downgraded to "in danger" if Queensland goes ahead with a slew of further port developments to expand the coal and natural gas industries. This article helps to lay out the political context and puts the debate in context, distinguishing between short and long term threats to the reef. It is quite possible to lose the wood of carbon emissions for the trees of maritime traffic. While a major accident would be a disaster, having an increasing number of coal ships successfully reaching their destinations ensures a long term catastrophe through warming and acidifying oceans. Australia's recently announced major marine reserve expansion, while praiseworthy, will do little to save the reef.

WA Forest collapse: "ecosystem change can be sudden, dramatic and catastrophic". Western Australia is rapidly losing its (remaining) forests. The south-west of Australia has experienced some of the most obvious changes in precipitation anywhere in the continent, with a fairly sudden step-change occurring around 1970: "Groundwater levels have fallen up to 11 meters in some forested areas, with larger decreases in populated areas."

Cane toads: A new development with the potential to start turning the tide against Australia's second most destructive introduced species. H/T Mick.

15 comments:

byron smith said...

RealClimate: Groundwater study critiqued.

byron smith said...

The Conversation: UN throws down the gauntlet on GBR.

byron smith said...

PhysOrg: Groundwater depletion in semi-arid regions of Texas and California threatens food security.

"Three results of the new study are particularly striking: First, during the most recent drought in California's Central Valley, from 2006 to 2009, farmers in the south depleted enough groundwater to fill the nation's largest man-made reservoir, Lake Mead near Las Vegas—a level of groundwater depletion that is unsustainable at current recharge rates. Second, a third of the groundwater depletion in the High Plains occurs in just 4% of the land area. And third, the researchers project that if current trends continue some parts of the southern High Plains that currently support irrigated agriculture, mostly in the Texas Panhandle and western Kansas, will be unable to do so within a few decades."

byron smith said...

NewScientist: Another example of sudden ecosystem change (also Australian).

byron smith said...

Grist: CSIRO report says climate change is already measurably affecting Australian oceans.

byron smith said...

DD: Coal boom threatens Great Barrier Reef.

byron smith said...

Australia's world-leading marine reserves now have stiff competition from Cook Islands and New Caledonia. I am guessing that Australia may have had some influence in this, though would be fascinated to know how much.

byron smith said...

Guardian: Massive expansion of nature reserves needed as part of efforts to prevent biodiversity collapse.

byron smith said...

CPD: Preserving Our Marine Wealth. A report from the Centre for Policy Development on the economic benefits of Australia's marine parks.

byron smith said...

SciDaily: Warmer waters affecting the GBR.

byron smith said...

Guardian: Oz govt promises to protect GBR.

byron smith said...

Conversation: Australia coy in report to UN on plans for GBR.

UN should declare GBR in danger.

"The reef has been assailed to such a degree that it now has only 14% coral cover – half what is was 27 years ago."

byron smith said...

Guardian: GBR report card - reef in decline.

byron smith said...

Guardian: GBR strategic assessment warns of declining health of the reef, especially the southern 2/3rds and names climate change as "the most serious long-term risk facing the reef".

byron smith said...

Guardian: Hunt approves coal port expansion at Abbot Point. This is the trigger UNESCO warned about. I hope they have the guts to follow through on their threat and downgrade the status of the GBR.