The Weather of the Future

Weather of the Future: Heat Waves, Extreme Storms, and Other Scenes from a Climate-Changed Planet

Heidi Cullen takes readers forty years forward in her survey of what is likely to happen in several areas of the world if we continue to burn fossil fuels. Her book is The Weather of the Future: Heat Waves, Extreme Storms, and Other Scenes from a Climate-Changed Planet. It is a highly effective communication to the lay person of what climate science predicts for the specific areas she has chosen to explore. Cullen, a climatologist, works as a senior research scientist for Climate Central, an organisation set up in 2008 to act as a central authoritative source for climate change information.

Before moving to the selected areas for closer examination she offers some lucid general introductory chapters, including a very useful explanation of the use of modelling in climate prediction. In response to the question of when the weather will start to reflect predictions about the climate she answers that it already has in extreme weather events. If greenhouse gases continue to rise, the way weather affects life on Earth will be far worse than anything we’ve ever seen before. ”Can we rally around this forty-year forecast for the good of the world, or will we wait until the levees break before we decide to act?

The first area Cullen surveys is the Sahel region of Africa.  She talks with climatologists who work on understanding the rainfall patterns and outlook for the region.  The picture is complex, but there is no doubt that the region is going to get warmer. All the models agree on that. They show some variation on the expected amount of rainfall, but it seems likely that the rainy season will start later and become shorter, with storms that will possibly become more intense. Pockets of resilience offer some hope from farmers who have turned to tree planting with considerable benefits to their crops and welcome extra income from the trees. But as Cullen takes her projections forward she remarks that there is only so much the trees can do against the increasing reality of climate change. Socially, climate change will become a threat multiplier as conflict spreads across the African continent in lockstep with temperature.

The next selected area is the Great Barrier Reef. Cullen talks with Joanie Kleypas, a marine ecologist and geologist who uses climate models to study the health of coral reefs. “I work on coral reefs, for God’s sake. The entire coral science community is depressed.” The chapter provides very clear accounts of the bleaching effect of warming oceans (“Bleached corals aren’t dead; they’re just starving.”) and the deleterious effect on coral growth from ocean acidification. The speed of both warming and acidification is likely to quickly outpace the conditions under which coral reefs have adapted and flourished through past changes. They are unlikely to be able to adapt fast enough. It’s not a good outlook. Cullen allows herself a detour to point to other and more dramatic effects of climate change that Australia is set to encounter – ferocious wildfires, pervasive drought, and unbreathable air. The lucky country looks anything but in coming decades.

The US is a leading per capita contributor to global emissions. It has not yet accepted the level of responsibility it carries. Other places, far less responsible and much poorer, are bearing the early consequences of global warming. But that doesn’t mean the US will remain exempt from any serious consequences, and it was good to see Cullen turning to her own country for two of her chapters, and driving home that message.  One of the places she selects is Central Valley, California.  The Sacramento-San Joaquin Delta is a focus of her attention here. It’s the hub of California’s water supply system. The Hollywood-style dream is that the Delta will be able to supply enough clean fresh water to help cities and crops increase “forever”, all without harm to the natural environment, she notes dryly. She speaks with a multidisciplinary team studying the Delta, which in reality has far more in common with New Orleans than with Hollywood. The details of the problems and threats are canvassed and the extreme vulnerability of California to coming water shortage exposed. Her other US focus is New York city. Here it will be energy blackouts which threaten as the average temperature increases over coming decades. The power grid is unsuited to climate extremes. The other major area not ready for what lies ahead is flood protection.  However planning is going on in New York to develop resilience to what the changed climate will deliver, and also to mitigate the city’s emissions.  Cullen imagines a time four years from now in which, following damage from a storm, a co-ordinated plan is finally adopted by an alarmed population and New York becomes a city obsessed with adapting to climate change. It clearly needs to.

Her other chapters look at more obviously and immediately vulnerable places. In the Arctic she examines the current experience of the Inuit in an area of Canada and in Greenland. Change is well under way as sea ice diminishes and permafrost melts. It brings with it not only the physical challenges to the Inuit ways but also severe cultural threats. In Greenland as the ice melts there’s the promise of wealth from resource extraction, and the ambiguities that come with it. Bangladesh is skilled in adaptation to change and experienced in flood management, but by 2050 with almost 25 per cent of the country under water as a result of rising seas and increasing tropical cyclones, accompanied by the slow and deadly seepage of saline water into wells and fields, Bangladesh will be in serious trouble. Millions of villagers will have to move to the city, and many are likely to cross illegally into India hoping to find work.

The value of Cullen’s book is that by focusing on specific places, and by talking with scientists who are devoting full attention to the problems climate change poses for those places, she brings the reader close up to inescapable realities. The details are spelt out. Moreover she does this by a lively narrative of her discussions with the scientists closely involved. Her book is not a dry account of scientific papers but a picture of the people working to understand, predict and prepare for what is in waiting for the populations in the areas she discusses. It’s a reminder too of the number and variety of people who now work on climate change-related issues.

The book recognises the adaptation capabilities being shown by some of the populations already affected by climate changes. It is with some reluctance that it acknowledges the possibility of defeat if high emission levels continue. They don’t need to continue, of course, but that is in the hands of policy makers. Cullen in conclusion examines two words in use in the science. One is unequivocal, used to describe the warming of the climate system. The other is irreversible, used to describe uncertain but all too possible eventualities. She uses the cutting down of the last tree on Easter Island, as imagined so vividly by Jared Diamond in his book Collapse, as an analogy for irreversibility. Unfortunately as yet the two words are not powerful enough in policy circles to shift the forecast for the future.

[More at: Fishpond (NZ), Amazon.com, Book Depository (UK, free shipping worldwide).]

Monday miscellany

I‘m going to be away from my desk for a few days this week, so here’s a few interesting things to read and reflect on. First up: Wellington’s hosting this year’s New Zealand Soil Carbon Conference at Te Papa from Wednesday to Friday. Keynote speakers are Tim Flannery and Christine Jones, and topics to be covered include:

  • The science behind climate change and soil carbon
  • The on-farm benefits of biological farming
  • How research can support innovative farmers
  • An overview of the new biological economy and market opportunities
  • Practical tips to build soil carbon, humus and soil biology
  • Future directions for NZ agriculture and extension services

Full programme here — Friday’s a field trip day. Sounds very worthwhile. If any HT readers are attending (or if the conference organisers are reading this), I’d be very happy to carry a report on events.

Adding to the long list of material debunking standard sceptic & crank claims about climate change, Deutsche Bank’s Climate Change Advisors (DBCCA) have produced a nicely referenced document (PDF), prepared for them by the Earth Centre at Columbia University. Here’s a sample from the executive summary:

Claim: Human society and natural systems have adapted to past climate change.

Response: Past climate changes have often been accompanied by migration, war, and disease. The growing human population will inevitably make environmental change more disruptive in the future, even in the face of increased technological prowess.

A couple of items from Nature News: in Collapse of the ice titans, NN interviews Richard Bates, recently returned from a summer sail along Greenland’s NW coast on the Gambo (more on that voyage at Jason Box’s Meltfactor.org blog) about the melt season at the Petermann and Humboldt glaciers. Ocean conveyor-belt model stirred up looks at a new paper in Nature Geoscience that finds greater than expected variability in the great ocean current network known as the Thermohaline Circulation (THC). Understanding the short term changes in THC flows will be important in attempts to model short term and regional climate change.

The Arctic sea ice looks to be fast approaching its summer minimum, heading for somewhere between 2008 and 2009 — making it the third lowest in the record. Best place to keep up with events is (as it has been all NH summer) Neven’s Arctic Sea Ice blog. The two boats (Northern Passage, Peter 1) attempting to circumnavigate the Arctic Ocean in a single season are both now heading for the southern route of the NW Passage. In the southern Beaufort Sea the Norwegian team are reporting high sea temperatures:

We are still surprised and worried about the high water temperature. At the moment we are registering around 7 to 8 degrees Celsius, which according to the experts is far higher than normal.

Also of interest for sea ice aficionados: a new paper in Quaternary Science Reviews looks at what we know of the history of Arctic sea ice. Coverage at Climate Central and Science Daily but here’s Climate Central talking to the NSIDC’s Mark Serreze:

“They’re telling us that there was maybe no ice during the Arctic summers 7,000 years ago, and also ice-free summers during the last interglacial 125,000 years ago.” Those were due to natural factors, most notably the changes in Earth’s orientation to the Sun that brought more sunlight to the Arctic in summer. This time, says the paper, there is no known natural explanation, and climate skeptics who claim the ice is rebounding after the 2007 low, he says, “are grasping at straws.”

And finally: the British government starts planning to adapt to inevitable warming (but offers no new money). Plus ça change…

Take a peek at Pukaki’s climate history

Irishmantreambasin.jpg

High in the Ben Ohau range to the west of Lake Pukaki in the South Island’s Mackenzie basin, the glacial moraines in the Irishman Stream Basin (Google Map) are providing important confirmation that the southern hemisphere warmed during a rapid northern hemisphere cooling event at the end of the last ice age. In a new paper in Nature, Glacier retreat in New Zealand during the Younger Dryas stadial Michael Kaplan and a team including three NZ scientists reconstruct the retreat of the glacier that used to fill the basin.

The team dated the sequence of moraines (piles of rock left by the retreating glacier) by measuring the “cosmogenic” beryllium isotope (10Be) in quartz crystals in the rocks — formed by bombardment by cosmic rays — giving a measure of how long the rocks have been exposed to the sky. By modelling the amount of ice in the valley at various moraine positions, they were able to reconstruct the glacier’s decline as the local climate warmed.

Why is this important? Because it’s another important bit of evidence in piecing together the sequence of events as the world warmed up from the last ice age — and in particular because the precise dating confirms that the Younger Dryas cold spell was not global in effect. From the abstract:

Our late-glacial glacier chronology matches climatic trends in Antarctica, Southern Ocean behaviour and variations in atmospheric CO2. The evidence points to a distinct warming of the southern mid-latitude atmosphere during the Younger Dryas and a close coupling between New Zealand’s cryosphere and southern high-latitude climate. These findings support the hypothesis that extensive winter sea ice and curtailed meridional ocean overturning in the North Atlantic led to a strong interhemispheric thermal gradient during late-glacial times, in turn leading to increased upwelling and CO2 release from the Southern Ocean, thereby triggering Southern Hemisphere warming during the northern Younger Dryas.

See also Science Daily. Ref: Kaplan et al. Glacier retreat in New Zealand during the Younger Dryas stadial. Nature (2010) vol. 467 (7312) pp. 194-197

[Edited to correct my original abysmal geography fail – wrong lake in the title]

The “inconsistencies” of Chris de Freitas

Auckland University associate professor Chris de Freitas (yes, that one) is a favourite of the NZ Herald opinion editor, regularly popping up in the paper to argue a sceptic line on climate change or, as has happened a couple of times recently, to talk about responses to earthquake disasters. Quite why the paper would go to CdF for the latter when there are many other better-qualified academics who could address the issue remains to be seen, but his article in response to the Canterbury quake in yesterday’s Herald was interesting. Compare and contrast CdF, 6/9/2010:

The focus on earthquake-disaster planning and crisis management is on risk reduction, readiness, response and recovery. In this context, government and local authorities have the responsibility to minimise social vulnerability and have a duty to promote community resilience through enlightened planning.

… with CdF, 1/5/09:

No one knows for sure what the future holds, but there are some good clues as to what’s going on. It hinges on growing evidence that natural influences on climate are in fact stronger than any man-made greenhouse effect. It may be premature to discard our anxiety over the threat of possible human-caused global warming, but this anxiety should not be based on ignorance of what science can tell us.

So for earthquake hazards, de Freitas is happy to argue for risk minimisation despite imperfect knowledge of the size of the risk (his piece looks into failed attempts to predict quakes), but when it comes to climate issues his argument is we shouldn’t do much because we don’t know enough!

Another example of the remarkable intellectual flexibility we have come to expect from the scientific advisor to NZ’s Climate “Science” Coalition. Or perhaps it’s simple hypocrisy. You decide…

Long way around the sea

With the northern hemisphere summer fading into autumn, time for a quick overview of Arctic events. The sea ice is nearing its annual low point, and appears to be heading for a minimum somewhere between 2009 and 2008 — 2007’s record minimum appears to be beyond reach. The latest batch of forecasts for the SEARCH exercise mostly agree, but it’s still a bit early to make a final call — reductions in extent can continue right up to the end of the month. This graph of sea ice extent (from the University of Bremen) puts the current situation in context (click to see a large, updated version):

Bremenextent030910.gif

Now let’s see what that data looks like on a map…

Continue reading “Long way around the sea”