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Category — Food security

New seeds of hope for Nepal’s farmers

Om Astha Rai

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Growing concern: in Nepal, 50% of arable land is planted with rice. Image: Sigismund von Dobschütz via Wikimedia Commons

Climate-resilient varieties of rice could help to protect crop yields from the ravages of droughts and floods caused by the increasingly erratic weather patterns in South Asia.

Farmers badly affected by changing weather patterns in South Asia now have the opportunity to improve food security by planting new varieties of rice capable of withstanding the impact of both severe droughts and floods.

This is particularly good news for countries such as Nepal, where around 65% of its more than 26 million people are involved in agriculture. Rice is the country’s most important crop, planted on more than 50% of its arable land.

And it comes at a time when new research using satellite imaging has highlighted the growing need to change agricultural practices in South Asia as higher average temperatures cause the reduction of crop yields on the Indo-Gangetic plain. [Read more →]

July 31, 2014   No Comments

Rising heat hits Indian wheat crop

Alex Kirby

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Feeling the heat: the yield from wheat harvests in India is falling. Image: Yann via Wikimedia Commons

Satellite imaging highlights the growing need to change agricultural practices in South Asia as higher average temperatures cause the reduction of crop yields on the Indo-Gangetic plain.

Researchers in the UK have established a link between changing climate and agriculture that could have significant consequences for food supplies in South Asia.

They have found evidence of a relationship between rising average temperatures in India and reduced wheat production, which was increasing until about a decade ago but has now stopped.

The researchers, Dr John Duncan, Dr Jadu Dash and Professor Pete Atkinson, all geographers at the University of Southampton, say an intensification is predicted for the recent increases in warmth in India’s main wheat belt that are damaging crop yields.

The greatest impact that the hotter environment has on wheat, they say, comes from a rise in night-time temperatures. [Read more →]

July 29, 2014   No Comments

Soils may absorb less CO2 than thought

Tim Radford

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Ferdynand Ruszczyc’s The Soil: The part played by the world’s soils in accounting for carbon dioxide is pivotal. Image: Via Wikimedia Commons

Researchers believe that natural processes are not as efficient in absorbing carbon dioxide and putting a brake on global warming as they had previously thought.

Scientists from the US, China and Ireland may have settled one big question about climate change: don’t rely on the soil microbes to help damp down the temperatures. They report in Sciencethat as carbon dioxide levels rise, and temperatures increase, so does the turnover of carbon in the soil.

That means the hope that global warming must mean more energetic plant growth and therefore greater carbon uptake in the soil, in a cycle that engineers like to call negative feedback, looks a bit forlorn.

Kees van Groenigen of Northern Arizona University and colleagues analysed results from 53 different studies of soil carbon measurements in forests, grasslands and farmers’ fields around the world to see how CO2 affects plant growth, soil activity and soil carbon.

They found that extra carbon dioxide in the atmosphere meant more input into the soil – nearly 20% more – but it also meant more turnover, up by more than 16%.

So if more went in, more was released, because the teeming microscopic fauna that inhabit the soil, recycle nutrients and redistribute plant nourishment also became more active.

“Our findings mean that nature is not as efficient in slowing global warming as we previously thought,” said Dr van Groenigen. “By overlooking this effect of increased CO2 on soil microbes, models used by the Intergovernmental Panel on Climate Change may have overestimated the potential of soil to store carbon and mitigate the greenhouse effect.” [Read more →]

May 2, 2014   No Comments

Heat extremes threaten crop yields

Tim Radford

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An undersized cob from a failed maize crop in Ghana which has suffered failed rains and rising temperatures. Image: By CIAT (NP Ghana23_lo Uploaded by mrjohncummings), via Wikimedia Commons

Yields of several major crops are likely to be seriously affected by rising temperatures, scientists say, with spells of extreme heat posing the greatest risk.

Rampant climate change driven by ever-rising levels of carbon dioxide in the atmosphere poses a serious threat to world food supply, according to a new study in Environmental Research Letters.

The hazard comes not from high average temperatures, but the likelihood of heat extremes at times when crops are most sensitive to stress. And the message is: those communities that rely on maize as a staple are more at risk than most.

Delphine Derying of the Tyndall Centre for Climate Change Research at the University of East Anglia in the UK and colleagues looked at one of the big puzzles of the coming decades: what will global warming do for crop yields?

It is not a simple question: climate change must mean more evaporation, more precipitation, longer growing seasons, more warmth, and higher levels of the carbon dioxide that plants exploit by photosynthesis (the process they use to convert light into chemical energy), so the consequence ought to be greater yields. But as every farmer knows, what matters most is the timing of all that warmth, rain, and those dry spells in which the harvest can ripen. [Read more →]

March 23, 2014   No Comments

Climate risks irreversible change

Alex Kirby

In a highly unusual intervention in the debate over climate policy, US scientists say the evidence that the world is warming is as conclusive as that which links smoking and lung cancer.

The American Association for the Advancement of Science (AAAS) says there is a “small but real” chance that a warming climate will cause sudden and possibly unalterable changes to the planet.

This echoes the words used in its 2007 report by the Intergovernmental Panel on Climate Change (IPCC), which said climate change might bring “abrupt and irreversible” impacts.

In a report, What We Know, the AAAS makes an infrequent foray into the climate debate. The report’s significance lies not in what it says, which covers familiar ground, but in who is saying it: the world’s largest general scientific body, and one of its most knowledgeable.

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A child with kwashiorkor, caused by evere protein deficiency: Child malnutrition may rise by about a fifth. Image: Dr Lyle Conrad, Centers for Disease Control and Prevention, via Wikimedia Commons

The AAAS says: “The evidence is overwhelming: levels of greenhouse gases in the atmosphere are rising. Temperatures are going up. Springs are arriving earlier. Ice sheets are melting. Sea level is rising. The patterns of rainfall and drought are changing. Heat waves are getting worse, as is extreme precipitation. The oceans are acidifying. [Read more →]

March 19, 2014   No Comments

Warsaw – Day 7: World ‘neglects climate impact on food’

Alex Kirby

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Harvesting beans in Ethiopia: Small farmers hold the keys to resilience. Image: USAID Africa Bureau via Wikimedia Commons

With the UN climate talks in Warsaw at their mid-point, a fringe meeting is debating the future of agriculture in a warming world. A senior scientist tells the Climate News Network of her deep misgivings for the future.

Global leaders are failing to respond to the threat posed by climate change to the growing challenge of feeding the world, a leading agricultural researcher says.

They do not treat the problem seriously, and they are ignoring the warnings of science about what is liable to happen.

Yet, she says, there is much more evidence available than there was a few years ago, and the future it describes is cause for great concern.

The criticism comes from Dr Sonja Vermeulen, who heads the CGIAR research programme on climate change, agriculture and food security (CCAFS).

She was speaking to the Climate News Network as the UN climate negotiations – the 19th conference of the parties to the Framework Convention on Climate Change, COP 19 – got under way in the Polish capital, Warsaw. [Read more →]

November 17, 2013   No Comments

Climate threat to Southern Africa’s crops

Kieran Cooke

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Woman farmer in Malawi: climate change is likely to jeopardise future crop yields. Image: Swathi Sridharan (ICRISAT)

Southern Africa could be among areas hardest hit by climate change. A rapidly expanding population is likely to add to future problems, says a new study.

The study, published by the International Food Policy Research Institute (IFPRI), and with contributions from scientists in countries across the southern Africa region, uses available data and a variety of models to examine likely agricultural developments, particularly related to crops, in the period to 2050.

Agriculture is the primary source of employment and income for most of the rural population in southern Africa. In Malawi about 40% of gross domestic product (GDP) comes from agriculture.  In Zimbabwe, about 80% of the population depends directly on agriculture.

More than 50% of agricultural land in the area is devoted to cereal crops, with maize accounting for more than 40% of the total harvested area. Millet and sorghum are also important crops, especially in drier areas. Some countries in the region, such as Botswana and Lesotho, already struggle to meet demand for maize and sorghum and have to import large amounts, mainly from South Africa.

The study says climate change, with rising temperatures and increasingly erratic rainfall patterns across much of the region, will likely cause a decline in average maize and sorghum yields. However, some areas, such as southern Mozambique, will see a growth in harvests. Wheat harvests could be particularly vulnerable to rising temperatures. [Read more →]

September 12, 2013   No Comments

Brazil: Climate change will impact food security

Jan Rocha

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Future harvests of monoculture crops such as soya beans could be severely reduced in Brazil. Image: Tiago Fioreze

Brazil’s standing as one of the world’s major producers and exporters of food could be severely threatened unless its farming methods are urgently adapted to take account of climate change.

Higher temperatures, drastic changes in rainfall, lower productivity, more blight and disease − these are just some of the expected consequences of climate change in Brazil if the projections of 345 scientists who make up the Brazilian Panel on Climate Change (PBMC) prove true.

They predict that if present trends in greenhouse gas emissions continue, average temperatures in Brazil will be 3º-6ºC higher by 2100 than they were at the end of the 20th century.

Rainfall patterns could change drastically, increasing by up to 30% in the south and south-east of the country, while diminishing by up to 40% in the north and north-east.

The forecasts, based on research over the last six years, are contained in a report that provides the most complete diagnosis yet of the future tendencies of the Brazilian climate. [Read more →]

September 3, 2013   No Comments