by Nature
by Nature

australia

Warmest since records began: 2009

Author: MATT CAWOOD
Via: Farm Weekly - online

NASA’s Goddard Institute for Space Studies (GISS) has placed 2009 as the warmest year in the Southern Hemisphere since records began 130 years ago, and the past decade as the warmest globally.

Globally, 2009 tied with 1998, 2002, 2003, 2006 and 2007 as the second warmest year on record after 2005, according to the GISS analysis of planetary temperatures.

The decade from January 2000 to December 2009 was clearly the warmest since modern instrumentation was introduced in 1880.

“There’s substantial year-to-year variability of global temperature caused by the tropical El Nino-La Nina cycle”, said GISS director James Hansen.

“But when we average temperature over five or ten years to minimize that variability, we find that global warming is continuing unabated.”

Over the past three decades, according to the GISS analysis, the global average temperature has increased 0.2 degrees Celsius a decade.

The Australian Bureau of Meterology (BoM) is waiting on the results of a similar analysis by the UK Met Office’s Hadley Centre, which BoM has traditionally used as a guide to global temperature trends.

The Hadley Centre analysis tends to be more conservative than GISS, according to BoM senior climatologist Dr Karl Braganza, because Hadley scientists leave out areas of the Arctic and Antarctic where climate monitoring stations are scarce.

GISS extrapolates data for these areas from the nearest monitoring stations in an attempt to deliver a fuller climate picture.

In the Hadley analysis, polar areas without monitoring stations are assumed to be warming at the same rate as the global average. GISS incorporates sea ice data from satellites that indicates the Arctic is warming faster than the rest of the planet.

Dr Braganza said while the two methods produce slightly different results - although often within a tenth or a hundredth of a degree - both show the same global warming trend.

A key driver of natural climate variability is the El Nino-La Nina cycle, which stems from the cyclic warming and cooling of the Pacific Ocean.

GISS and BoM climatologists believe the El Nino of late 2009 combined with greenhouse gas-driven warming to produce an unusually warm year in 2009.

“The unusual thing about this El Nino when it got going around mid-2009 was that Pacific ocean temperatures were already very warm, which was likely a continuation of the greenhouse warming effect,” Dr Braganza said.

That warmth across the Pacific generated rain, which counteracted the usual El Nino drying effect on eastern Australia for several months. But as the year went on, across eastern Australia as a whole it was very dry.

“Tasmania got some good rainfall, and Victoria had two or three rainfall events, but they were just weather events. Typically during an El Nino we get less of them.

“When you are talking about climate, you’re talking about what history can tell you might happen over a particular stretch of time–but during an El Nino, you can still get a good rainall event coming through with the normal weather that gives a bit of relief.”

The global warming trend, which is reflected in the warming of the Australian temperature record, appears to be continuing despite the deepest recorded solar minimum.

During solar maximums, high sunspot activity is generally correlated with higher surface temperatures on Earth. Solar minimums, or low sunspot activity, are generally related to cooler temperatures, but this is not the case during the current minimum.

Aerosols, particularly sulfate aerosols produced by volcanoes, are also known to cool global temperature by reflecting sunlight, but aerosols appear not to have played a significant role during 2009.

Source: http://fw.farmonline.com.au/news/nationalrural/agribusiness-and-general/general/warmest-since-records-began-2009/1734382.aspx?storypage=1

Peak phosphorous: mankind’s latest threat

Author: MATT CAWOOD
Source: http://fw.farmonline.com.au

SOME believe that dwindling supplies of potable water is humanity’s great resource challenge; others think it is the imminent prospect of “peak oil”.

But an equally important milestone in modern history will be an inevitable tightening of global supplies of phosphorus.

Phosphorus has underpinned the leaps made in agricultural productivity since World War II, and the world’s economies and population levels have become dependent on a continous supply of the element.

Unlike nitrogen, which can by synthesised from the air, or the use of renewable energy to substitute for fossil fuels, there is no substitute for phosphorus. All the world’s phosphate fertilisers come from mined phosphate rock, making it a finite resource.

Various analyses suggest “peak phosphorus” - the point at which supply falls behind demand - will occur around 2040, with all currently known reserves potentially exhausted within 50 to 100 years.

However, University of Technology Sydney researchers Dana Cordell and Stuart White warn that for most countries, a phosphorus squeeze is likely to come much sooner.

Demand for phosphorus is growing in line with population growth, and is being pushed higher by greater consumption of meat in countries like China and India.

(Based on European practices, the Swedish Environmental Protection Agency estimates that a vegetable-based diet uses 0.6 kilograms of phosphorus per person per year, compared with 1.6 kg for a meat-based diet.)

Few nations have access to enough phosphorus to supply their own agricultural needs: in fact, most of the world’s known phosphate reserves are controlled by China, the United States and Morocco.

China has the largest reported reserves, but in 2008, at the height of the food crisis, China’s central government introduced a 135 per cent tariff on exports to protect domestic supply.

The US, historically the world’s largest consumer, importer and exporter of phosphate fertilisers, is now thought to have only about 25 years of domestic phosphate reserves left. US fertiliser manufacturers are importing large quantities of phosphate from Morocco.

Morocco supplies more than a third of the world’s phosphate, but it is an industry that stands on politically unstable ground. Much of Morocco’s phosphate comes from the disputed territories of the Western Sahara, an activity that has been condemned by the United Nations.

Phosphorus may be in finite supply, and that supply politically uncertain, but Australia’s agricultural and food systems remain highly inefficient users of the fertiliser.

Dana Cordell calculates that only two per cent of phosphate fertiliser applied in Australia is eaten in locally-consumed food.

Up to 75 per cent of P fertiliser is locked-up in agricultural soils. About 20 per cent of applied fertiliser is exported in farm produce, and a minor amount is leached into waterways, contributing to nutrient overload or carried out to sea.

One researcher has estimated that of the billion tonnes of phosphorus mined since 1950, about a quarter now lies in water bodies or landfills.

Each year, Ms Cordell says, humans eat about three million tonnes of phosphorus, and excrete close to 100 per cent of it.

In some countries, that has led to serious investigation of recycled urine as a source of agricultural phosphorus.

Urine is “essentially sterile”, and contains nitrogen, phosphorus and potassium in the correct ratios for plant growth.

If all human urine was recycled, according to Jan-Olof Drangert of Linköping University in Sweden, where Dana Cordell also studies, it could supply half the phosphorus needs of the world’s cereal crops.

Two Swedish municipalities have mandated that all new toilets must divert urine away from solid waste. The urine is collected in tanks either at the house, or in a communal collection point, and picked up once a year by farmers who use it as fertiliser.

However, in countries like Australia, with a large land area and a relatively small population, nutrient recycling can at best provide five per cent of the nation’s phosphorus needs.

All article on http://fw.farmonline.com.au/news/nationalrural/agribusiness-and-general/general/peak-phosphorous-mankinds-latest-threat/1729835.aspx?storypage=1

Live export demand defies rising prices - Australia

Author: TRAVIS KING

DESPITE the sharp rise in sheep export prices over the past eight months, demand for Australian sheep in the Middle East is holding strong.

And this demand is not expected to drop off according to Livecorp livestock services manager Peter Dundon.

Mr Dundon, who is based in Bahrain, said if Australian producers were debating whether they should be sticking with sheep or not, he would strongly suggest they do.

“While there is some resistance to the higher prices, importers are still keen to source Australian sheep simply because of the food security issue,” Mr Dundon said.

“While the fact that there are higher prices has seen some importers look to northern Africa to source sheep, no one can guarantee supply like Australia can.

“Bahrain demands 2500 sheep per day and Australia supplies 95 per cent of that market.

“If the trade to Bahrain stopped tomorrow, a whole lot of people would not have access to fresh meat.

“Somalia is probably our biggest competitor and are closest to Australian sheep in price, but Somalian sheep are about half the weight. They dress out at 11 kilograms as opposed to Australian sheep that have a 21-23kg carcase weight.

“Northern African countries also continually have issues with Foot and Mouth Disease and Rift Valley Fever and that disrupts supply.”

Mr Dundon admitted that there had been a marked change in the composition of the sheep that have been exported live to the Middle East in the past five years.

“We are now sending lighter sheep than we used to, but that is a reflection of the changing Australian sheep flock,” he said.

“Sheep are now being turned off at a younger age, so they are going to be lighter.

“Weights are also influenced by seasons. Seasonal conditions over the last couple of years have probably contributed to lighter weight sheep coming through, but at certain times of the year there are good heavy wethers sent over.

“I think if there is a readjustment to the Australian sheep flock and more people go back into sheep you will start to see heavier weights coming through again.”

Mr Dundon said there were more ewes being exported now compared to five years ago.

“This is concerning because, while some importers are happy to take them, we would rather see those ewes remaining in Australian paddocks and being used for breeding,” he said.

“The fact more ewes are now exported is an indication Australian farmers are going out of sheep and we want more sheep being produced not less.”

Source: http://fw.farmonline.com.au/news/state/livestock/sheep/live-export-demand-defies-rising-prices/1725447.aspx?src=enews

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