On fire inside a snowball

Fire: NOAA’s National Climate Data Centre has posted its report on global climate for July (press release). The combined global land and sea surface temperature of 16.5ºC was the second warmest in the NOAA record, 0.66°C above the average for the last 100 years of 15.8°C. The January to July period was the warmest in the record. The map below shows the anomalies for the month — spot the heatwave in Russia.

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Meanwhile, NASA’s Goddard Institute for Space Studies (GISS) has posted its take on the the July numbers: What Global Warming Looks Like. Click on the thumbnail image at the top of the post to see their map of July temperatures. One striking point they comment on:

…the area warmer than climatology already (with global warming of 0.55°C relative to 1951-1980) is noticeably larger than the area cooler than climatology. Also the magnitude of warm anomalies now usually exceeds the magnitude of cool anomalies.

GISS also note that the 12-month running mean (below) of global temperature is well into record territory, and that it’s possible that calendar 2010 could also set a record.

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Meanwhile, up North….

Continue reading “On fire inside a snowball”

Farming’s future in NZ: adapt or decline

How will our land-based primary industries manage the climate changes ahead? That’s the question addressed by chapter 3 in Climate Change Adaptation in New Zealand (pdf download here). The general impression given is that they won’t fare too badly provided appropriate adaptive measures are taken. The chapter, contributed by a team of nine, reports on modelling examples from the three major areas of forestry, arable farming and pastoral farming. It’s apparent that there is a level of complexity to farming operations which is very difficult to embrace in any study and the writers make it clear that much ongoing research will need to be undertaken. I’ll pick out a few salient points from the paper.

 

So far as forestry is concerned productivity is likely to be affected by changed CO2 levels, rainfall and temperature. Fire danger will increase in most areas of New Zealand. Increased severe winds are also predicted in some parts of the country. Pests and fungal diseases are likely to be strongly affected and the impacts of weeds and fungal pathogens could change, as could the establishment and distribution of insect pests.

The forestry modelling reported was focused on two common fungal diseases which affect forest productivity. One of the two diseases responds positively to aerial applications of copper oxychloride, and there may need to be changes to the way these are made as risk areas are identified. Other adaptation options for both diseases might include developing disease resistant genotypes, changing the regimes to modify the within forest microclimate (especially air movement and humidity), changing the tree species totally on at risk sites, and possibly moving the forests to less risky sites as the climate changes.

Adaptation strategies in general will involve normal forest practices and, provided a good understanding of the changes needed is obtained, the study concludes we should be able to maintain the health and productivity of our forests.

Arable farming is likely to benefit from climate change, provided nutrients and water supply are not limited. (That  struck me as a big proviso.) The advantages result from a number of factors. One is the fertilising effect of increased CO2 . Another is the rise in temperature causing crops to grow faster, be harvested earlier, and leave more options for subsequent crops. A warmer drier spring means soil dry enough for earlier cultivation and sowing operations.  An extended frost free period enables frost-sensitive crops to extend their range. And so on. A model run of one crop showed a 16% increase in yield by 2090 under the high carbon scenario and a 3 week earlier harvest.

But the water and nutrient caveat is important, particularly as most cropping occurs on the east coast, which is expected to see more hot, dry weather. Irrigation systems will need to be efficient, and crops with a deeper root system may fare better.  For although climate change increases yield potential and management flexibility in systems that have good water availability, it does the opposite for dryland systems and those with limited irrigation.  The paper notes that there remains significant uncertainty around the impacts of climate change on water flows in the major alpine rivers which underpin the east coast irrigation water supply.

Pastoral farming, the biggest contributor to New Zealand’s agricultural exports, was approached through modelling a Manawatu dairy farm. It was modelled on a single mid-range climate change scenario. Two soil types were modelled, clay and sand. Pasture production increases, especially between 2000 and 2030, were predicted, particularly in late winter, spring and summer.  Potentially this is due to increased temperatures and solar radiation and increased prevalence of C4 (warm season) grasses. But the C4 grasses led to a reduction in pasture quality during summer and spring.

Unadapted systems resulted in a decline in milk solids production per cow and per hectare in both 2030 and 2080, compared with 2000.  The picture changed when adaptation measures were undertaken. Key adaptation measures included a range of farm management decisions which included earlier calving and increased stocking rates.  With such measures the paper reported adaptation can be profitable and turn the potential negative of lower pasture quality into the positive of more production.  However the writers acknowledge that they did not consider the impacts of the recommended adaptations on significant environmental issues. More cows may increase nutrient and greenhouse gas losses from the farm.

It was such consequences that left me wondering how robust some of the adaptation measures may prove to be. Currently more cows mean more methane. Adaptation measures which also increase greenhouse gas emissions will surely be looked at askance by 2030. And the prospect of more nutrient run-off is fraught with environmental consequences. For arable farming the irrigation issue carries many questions likely to prove difficult of resolution. However there will no doubt be closer examination of these and other adaptation possibilities as time proceeds.  Presumably Federated Farmers will eventually emerge from its bunker and share in the process. The paper speaks of farm producers in New Zealand as innovative and adaptable and able to live with climate variability. But it points to climate change as more than variability when it goes on to ask whether those producers will be adaptable enough to manage a changing as well as variable climate. In the current mind-set of denial displayed by much of the farming community that seems to me an open question.

Lester Brown: Russian heat hits world grain supplies

One of the things that persuaded Gwynne Dyer that it was time to write his book Climate Wars was the realisation that “the first and most important impact of climate change on human civilization will be an acute and permanent crisis of food supply”. He’s not the only one to recognise that. Many of us hearing about what the Russian heat wave is doing to crops have no doubt been wondering what the effect of so much loss might be on global supplies. Right on cue Lester Brown, whose Plan B books always lays great stress on food reserves, has produced  an updateon what the failed harvest in Russia might mean.

 

“Russia’s grain harvest, which was 94 million tons last year, could drop to 65 million tons or even less. West of the Ural Mountains, where most of its grain is grown, Russia is parched beyond belief. An estimated one fifth of its grainland is not worth harvesting. In addition, Ukraine’s harvest could be down 20 percent from last year. And Kazakhstan anticipates a harvest 34 percent below that of 2009. (See data.)”

He notes that the heat and drought are also reducing grass and hay growth, meaning that farmers will have to feed more grain during the long winter. Moscow has already released 3 million tons of grain from government stocks for this purpose. Supplementing hay with grain is costly, but the alternative is reduction of herd size by slaughtering, which means higher meat and milk prices.

The Russian ban on grain exports and possible restrictions on exports from Ukraine and Kazakhstan could cause panic in food-importing countries, leading to a run on exportable grain supplies. Beyond this year, there could be some drought spillover into next year if there is not enough soil moisture by late August to plant Russia’s new winter wheat crop.

The grain-importing countries have in recent times seen China added to their list. In recent months China has imported over half a million tons of wheat from both Australia and Canada and a million tons of corn from the US. A Chinese consulting firm projects China’s corn imports climbing to 15 million tons in 2015. China’s potential role as an importer could put additional pressure on exportable supplies of grain.

The bottom line indicator of food security, Brown explains, is the amount of grain in the bin when the new harvest begins. When world carryover stocks of grain dropped to 62 days of consumption in 2006 and 64 days in 2007, it set the stage for the 2007–08 price run-up. World grain carryover stocks at the end of the current crop year have been estimated at 76 days of consumption, somewhat above the widely recommended 70-day minimum. A new US Department of Agriculture estimate is due very soon, which will give some idea of how much carryover stocks will be estimated to drop as a result of the Russian failure.

We don’t know what all this will mean for world prices. The prices of wheat, corn, and soybeans are actually somewhat higher in early August 2010 than they were in early August 2007, when the record-breaking 2007–08 run-up in grain prices began. Whether prices will reach the 2008 peak again remains to be seen.

Brown performs the obligatory ritual of acknowledging that no  single event can be attributed to global warming, though I would have thought that by now that proviso could be taken as read. It’s surely more important to affirm, as of course he does, that extreme events are an expected manifestation of human-caused climate change, and their effect on food production must be a major concern.

“That intense heat waves shrink harvests is not surprising. The rule of thumb used by crop ecologists is that for each 1 degree Celsius rise in temperature above the optimum we can expect a reduction in grain yields of 10 percent. With global temperature projected to rise by up to 6 degrees Celsius during this century, this effect on yields is an obvious matter of concern.”

Demand isn’t going down to match the reduction:

“Each year the world demand for grain climbs. Each year the world’s farmers must feed 80 million more people. In addition, some 3 billion people are trying to move up the food chain and consume more grain-intensive livestock products. And this year some 120 million tons of the 415-million-ton U.S. grain harvest will go to ethanol distilleries to produce fuel for cars.”

And the obvious conclusion:

“Surging annual growth in grain demand at a time when the earth is heating up, when climate events are becoming more extreme, and when water shortages are spreading makes it difficult for the world’s farmers to keep up. This situation underlines the urgency of cutting carbon emissions quickly—before climate change spins out of control.”

There’s a podcast in which Lester Brown speaks at greater length, elaborating the matters covered in his written update, and amongst other things commenting on how we might be thankful, from a global grain harvest perspective, that it was Moscow and not Chicago or Beijing which experienced temperatures so far above the norm. The grain loss would have been much higher in either case.

It’s worth adding that while the Russian event is dramatic in terms of its obvious impact on exports of grain globally, there are plenty of other places where food production is threatened by extreme events or by other  trends which are in line with climate change predictions. It is impossible to look at the vast flooding of land in Pakistan and not wonder how they will cope with the washing away of millions of hectares of crops — there have been “huge losses” according to the BBC.

“We need to cut carbon emissions and cut them fast.”

Fire and rain

The last few weeks have seen some extraordinary weather events around the world: relentless extreme heat in Russia, biblical flooding in Pakistan and devastating landslides in China. Tens of millions of people have had their lives disrupted and thousands have died, and — beyond reasonable doubt — global warming is playing a part in creating these extremes. But how much of a part? Michael Tobis asked this question in a recent post:

Are the current events in Russia “because of” “global warming”? To put the question in slightly more formal terms, are we now looking at something that is no longer a “loading the dice” situation but is a “this would, practically certainly, not have happened without human interference” situation?

The answer, at least in the case of the current extremes, would appear to be yes.

Continue reading “Fire and rain”

It breaks

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The Petermann Glacier in northwest Greenland has calved a massive “ice island” from its floating tongue (the largest in northern hemisphere), as the MODIS image above demonstrates. The island is approximately 260 square kilometers in area, making it equivalent to (arbitrary choice of geographical comparison appropriate to blog) eleven Rangitoto Islands (or four Manhattans, or about one eightieth of the area of Wales), and broke off at the end of last week. It contains enough fresh water (being nearly 200m thick) to keep the USA supplied with tap water for 120 days. NOAA’s National Ice Centre provides another view, with the ice island outlined in red:

Continue reading “It breaks”