Stories tagged: yields

NASA Study Links Extreme Weather Events to Global Warming

A NASA study has found that recent extreme weather events, including last year’s Texas heat wave and the Russian heat wave of 2010, are very likely to be the consequence of global warming.

The findings, published last week in the scientific paper Proceedings of the National Academy of Sciences, analyse mean summer temperatures since 1951 and show that the odds have increased over the years for “hot”, “very hot” and “extremely hot” summers. From the period between 1951 and 1980, the study shows how extremely hot temperatures covered less than 0.2% of the planet, whereas today those temperatures cover about 10% of the land area.

NASA climatologists have long collected data on global temperature anomalies, which describe how much warming or cooling regions of the world have experienced when compared with the 1951 to 1980 base period. In this study, the researchers employ a bell curve to illustrate how those anomalies are changing.

Led by one of NASA’s principal climate scientists, James. E. Hansen says:

“This is not a climate model or a prediction but actual observations of weather events and temperatures that have happened. Our analysis shows that, for the extreme hot weather of the recent past, there is virtually no explanation other than climate change.”

Hansen says this summer is shaping up to fall into a new category, as statistics from the National Oceanic and Atmospheric Administration (NOAA), show July 2012 to be the single hottest month ever recorded in the United States. He says:

“Such anomalies were infrequent in the climate prior to the warming of the past 30 years, so statistics let us say with a high degree of confidence that we would not have had such an extreme anomaly this summer in the absence of global warming.”

In addition to NASA’s analysis, a second release of data findings from the Berkeley Earth Surface Temperature project found that average Earth surface temperature has risen by 1.5 °C over the past 250 years. The study shows a correlation between temperature records and recent atmospheric carbon dioxide level increases and points to logical reasoning that recent earth warming is anthropomorphic. This is demonstrated in one of Berkeley’s key findings charts below.

The two bodies of data validation above may help to settle ongoing controversy about the effects of climate change amongst scientists and political leaders. The new data could influence policy maker’s negotiations during key summits, such as in COP 18 in December, about how to best approach rising levels of CO2 in the atmosphere.

Information on agriculture and climate change can be found on Farming First’s website.



New Salt Tolerant Wheat Offers Farmers Higher Yields in Saline Soils

CSIRO, Australia’s national science research agency, have achieved a major breakthrough for wheat farmers in salt-affected areas through developing a salt-tolerant durum wheat that yields 25 per cent more grain than other varieties in saline soils.

High soil salinity is a major environmental issue whose effects can cause difficulties for farmers growing crops in salt-affected areas. Most crops do not grow well on soils that contain salts and subsequently farmers lose large amounts of yield.

The CSIRO research team used traditional breeding techniques, involving molecular markers, to introduce salt tolerant genes into durum wheat lines. The salt tolerant genes work by limiting the passage of sodium from the roots to the shoots of the plant, preventing its passage to the leaves where it can be toxic to the plant.

According to the Food and Agriculture Organisation, 17 million hectares of durum wheat are cultivated worldwide, with 60 per cent of cultivation taking place in developing counties in regions including the Middle East, North Africa, Latin America and central India.

This new variety will allow wheat farmers to cope with high salinity levels in the soil and achieve higher yields of their crop. The scientists have said they will make the enhanced durum wheat freely available to the developing world.

FAO Warns that World Food Output Must Rise by 70%

A recent announcement by the FAO states that world food output must rise by 70% by 2050 to meet projected demand from a growing population and changing diets.

Global cereal demand must increase by about 50%, from 2.1 billion tonnes today to 3 billion tonnes by 205.  Over the same period, meat output must increase by almost 75% by 2050 to 470 million tonnes.

A massive 90% of the needed output is expected to come from higher yields, but the area of land under cultivation is also expected to grow by 120 million hectares.  These increases are most likely to occur in developing regions with large supplies of land per capita, such as sub-Saharan Africa and Latin America.

Improving Yields in Zambia through Conservation Agriculture

In many countries where soil has been degraded or where farmers face difficult conditions, conservation agriculture has also been shown to improve yields through improved soil quality.

For example, in Zambia, a sample of 125 hand-hoe farmers using conservation farming in areas where land had been degraded was found to produce 1.5 tonnes more maize and 460 kg more cotton per hectare than did farmers practicing conventional ox-plough tillage.

Improving Yields through Better Access to Seeds and Pesticides

GM crops and crop protection products can help increase yields by limiting losses.

Since 1996, the average yield impact across the total global area planted with insect resistant traits over the 11 year period has been +5.7 percent for corn traits (or an added 47 million tonnes of corn) and +11.1 percent for cotton traits (or an added 4.9 million tonnes).

In some countries, the benefits can be much higher, such as in India, where yields from cotton have increased by 54%.