The impact of climate change on global crop production is likely to be worse than previously predicted, scientists will say at a Royal Society discussion meeting in London today (Tuesday 26 April 2005).

A two-day international meeting entitled “Food Crops in a Changing Climate” will bring together world-class scientists in the fields of meteorology, climate science and agriculture, to discuss the impacts of a changing climate on the productivity of staple food crops, grown throughout the world. Importantly, it will consider how best to forecast these impacts using observations and modelling techniques. The meeting will focus largely on tropical countries where most of the world’s food is grown and where people are most vulnerable to climate change.

Results will be presented from a series of large-scale field experiments on crops such as maize, rice, soyabean and wheat, that show how increasing temperatures, drought and ground-level ozone concentrations (as predicted for the coming century*), will result in substantial reduction in crop yields, outweighing the beneficial fertilisation effects currently predicted from rising levels of atmospheric carbon dioxide.

Professor Steve Long from Illinois University said: “Growing crops much closer to real conditions has shown that increased levels of carbon dioxide in the atmosphere will have roughly half the beneficial effects that were previously hoped for in the event of climate change. In addition, ground-level ozone, which is also predicted to rise but has not been extensively studied before, has been shown to result in a loss of photosynthesis and 20% yield loss.”

He continued: “Both these results show that we need to seriously re-examine our predictions for future global food production as they are likely to be far lower than previously estimated.”

Additionally, studies by scientists from the UK and Denmark show that just a few days of hot temperatures can severely reduce the yield of major food crops such as wheat, soyabean, rice and groundnuts, if they coincide with the flowering of these crops. These results suggest that there are particular thresholds above which crops become very vulnerable to climate change.

On a more positive note, the meeting will highlight new developments in forecasting techniques, the basis of which can act as early warning systems of famine for vulnerable countries. For example, a team from the NCAS Centre for Global Atmospheric Modelling and the Department of Agriculture at the University of Reading will demonstrate a new forecasting system that incorporates a state-of-the-art climate prediction model with a model that simulates crop growth under varying environmental conditions. They will show how this can be used to predict the yield of annual crops in countries such as India, for the next 50 -100 years, under a changing climate. Such information can be used by policy makers to aid future planning for climate and crop responses, and for assessing future vulnerabilities across the globe.

A report from this meeting will be made available to inform discussions at the G8 summit meeting at Gleneagles in July, with particular reference to food security in Africa.

Original press release: Impact of Climate Change on Crops Worse Than Previously Thought (Royal Society News)

A re-elected Labour government would put nuclear power back on the agenda in an effort to meet targets on climate change, government sources have said.

The sources told BBC News Tony Blair wanted a national debate on the issue.

He would raise the issue when ministers responded to a climate change policy review in June or July, they said.

The Tories say there should be new nuclear stations provided they meet cost and waste concerns but the Lib Dems oppose the idea.

Complete news release: Blair ‘to debate nuclear power’ (BBC News)

Using a new electrically-assisted microbial fuel cell (MFC) that does not require oxygen, Penn State environmental engineers and a scientist at Ion Power Inc. have developed the first process that enables bacteria to coax four times as much hydrogen directly out of biomass than can be generated typically by fermentation alone.

Dr. Bruce Logan, the Kappe professor of environmental engineering and an inventor of the MFC, says, “This MFC process is not limited to using only carbohydrate-based biomass for hydrogen production like conventional fermentation processes. We can theoretically use our MFC to obtain high yields of hydrogen from any biodegradable, dissolved, organic matter — human, agricultural or industrial wastewater, for example — and simultaneously clean the wastewater.

“While there is likely insufficient waste biomass to sustain a global hydrogen economy, this form of renewable energy production may help offset the substantial costs of wastewater treatment as well as provide a contribution to nations able to harness hydrogen as an energy source,” Logan notes,.

The new approach is described in a paper, ‘Electrochemically Assisted Microbial Production of Hydrogen from Acetate,’ released online currently and scheduled for a future issue of Environmental Science and Technology. The authors are Dr. Hong Liu, postdoctoral researcher in environmental engineering; Dr. Stephen Grot, president and founder of Ion Power, Inc.; and Logan. Grot, a former Penn State student, suggested the idea of modifying an MFC to generate hydrogen.

In their paper, the researchers explain that hydrogen production by bacterial fermentation is currently limited by the “fermentation barrier” — the fact that bacteria, without a power boost, can only convert carbohydrates to a limited amount of hydrogen and a mixture of “dead end” fermentation end products such as acetic and butyric acids.

However, giving the bacteria a small assist with a tiny amount of electricity — about 0.25 volts or a small fraction of the voltage needed to run a typical 6 volt cell phone — they can leap over the fermentation barrier and convert a “dead end” fermentation product, acetic acid, into carbon dioxide and hydrogen.

Logan notes, “Basically, we use the same microbial fuel cell we developed to clean wastewater and produce electricity. However, to produce hydrogen, we keep oxygen out of the MFC and add a small amount of power into the system.”

In the new MFC, when the bacteria eat biomass, they transfer electrons to an anode. The bacteria also release protons, hydrogen atoms stripped of their electrons, which go into solution. The electrons on the anode migrate via a wire to the cathode, the other electrode in the fuel cell, where they are electrochemically assisted to combine with the protons and produce hydrogen gas.

A voltage in the range of 0.25 volts or more is applied to the circuit by connecting the positive pole of a programmable power supply to the anode and the negative pole to the cathode.

The researchers call their hydrogen-producing MFC a BioElectrochemically-Assisted Microbial Reactor or BEAMR. The BEAMR not only produces hydrogen but simultaneously cleans the wastewater used as its feedstock. It uses about one-tenth of the voltage needed for electrolysis, the process that uses electricity to break water down into hydrogen and oxygen.

Logan adds, “This new process demonstrates, for the first time, that there is real potential to capture hydrogen for fuel from renewable sources for clean transportation.”

The Penn State researchers were supported by grants from the National Science Foundation, the U.S. Department of Agriculture, the Penn State Huck Life Sciences Institute and the Stan and Flora Kappe Endowment.

Original press release: Microbial Fuel Cell: High Yield Hydrogen Source and Wastewater Cleaner (Penn State University)

Room temperatures in Beijing government offices will be kept above 26 degrees Celsius this summer to help reduce strain on electricity supplies, says an order issued by the municipal government.

“We will continue to experience an electricity shortage this year, despite the rapid growth of generating capacity,” says Wang Yonggan, secretary-general of the China Electricity Council, an industry association. He says the deficit will be much lower this summer compared to last year.

Power shortages have become a major issue in many parts of the country since 2003. Nineteen out of 31 province-level regions on the Chinese mainland suffered power shortages in 2003, while it increased to 24 in 2004.

The order from Beijing also says different electricity prices will be implemented to encourage businesses to use electricity in off-peak hours.

It also asks government employees to form the habit of turning off lights when they leave offices for the day.

Guangdong Province introduced a new electricity rate system on April 1, enlarging the gap between peak-hour electricity prices and off-peak hour prices.

Guangzhou, the provincial capital, adopted a policy of protecting premium businesses. Several high-polluting small businesses in Zengcheng and Conghua have been ordered to stop production.

The Inner Mongolia Autonomous Region has reshuffled the industrial sector to promote economical use of electricity.

Analysts say electricity supply will meet demand in 2006.

Original press release: Beijing to Keep a Lid on Climate in Offices (China Daily)

The Institution of Civil Engineers (ICE) and the Renewable Power Association (RPA) today issued a joint report showing the huge potential for greater generation of energy from waste. The report, Quantification of the Potential Energy from Residuals in the UK, concludes that there is the opportunity for certain types of waste to produce up to 17% of electricity generated in the UK by 2020.

Almost 30 million tonnes of household rubbish was sent to landfill in England alone in 2003. The report states that more than half of this rubbish could be used to create enough power to light 2 million homes each year. A large majority of this waste is recognised in EU law as a source of renewable energy.

Peter Gerstrom, Chairman of ICE’s Waste Management Board, commented, “Instead of burying rubbish that is left after recycling it can be used to create electricity through a variety of measures. We are not generating enough renewable electricity, which means that the UK will not reach the EU Renewables Directive target of producing 10% of our electricity from renewable sources by 2010. We are even less likely to reach the next target of having 20% provided by renewables by 2020.”

“Year on year the UK is producing more waste. Waste into energy will have environmental benefits by reducing the rubbish mountain. It also has the added bonus that recycling residual biodegradable waste in this way is an effective way of hitting the targets in the EU Landfill Directive.”

“The UK should be taking the opportunity to harness this energy as this will boost our environmental performance by increasing our use of renewable power and reduce the UK�s reliance on landfill. This will not happen in the current climate.”

“The findings of this report should be of interest to the Government as the current DTIconsultation Renewables Obligation Review, published 4 April 2005, has within its remit the opportunity to consider allowing producers of energy generated from waste to receive Renewable Obligation Certificates (ROCs).”

Gaynor Hartnell, Director of Policy at RPA, said, “Many of our European neighbours excel at both recycling and energy recovery. Producing energy from waste after recycling targets have been achieved is environmentally sound and will help us meet both our renewables targets and help us minimise the amount of waste going to landfill. It also helps with energy security, through reducing dependence on energy imports.”

“The UK should seek to limit the unsustainable option of landfill for Commercial and Industrial Waste, to bring us in line with the rest of Europe. This would encourage greater recycling and secure sufficient amounts of biodegradable waste to realize the 17% potential identified in the report. ICE and RPA are calling for government support to encourage the development of this energy resource.”

Peter Gerstrom continues, “It is patently not in the UK’s interest to allow the energy, enough to power the population of Wales and Northern Ireland every year, to go to waste by being buried. Radical thinking about alternative energy, such as that highlighted in this report, is required to ensure the safety and diversity of the UK energy supply.”

Original press release: Energy From Waste Must Not be Overlooked Say Industry Experts (Renewable Power Association)

A NASA funded study has found a decline in winter and spring snow cover over Southwest Asia and the Himalayan mountain range is creating conditions for more widespread blooms of ocean plants in the Arabian Sea.

The decrease in snow cover has led to greater differences in both temperature and pressure systems between the Indian subcontinent and the Arabian Sea. The pressure differences generate monsoon winds that mix the ocean water in the Western Arabian Sea. This mixing leads to better growing conditions for tiny, free-floating ocean plants called phytoplankton.

Lead author of the study is Joaquim Goes. He is a senior researcher at the Bigelow Laboratory for Ocean Sciences, West Boothbay Harbor, Maine. Goes and colleagues used satellite observations of ocean color to show phytoplankton concentrations in the Western Arabian Sea have increased by more than 350 percent over the past seven years. The study is in this week’s SCIENCE magazine

When winter and spring snow cover is low over Eurasia, the amount of solar energy reflected back into the atmosphere is less. A decline in the amount of snow cover means less of the sun’s energy goes towards melting of snow and evaporation of wet soil. As a result the land mass heats up more in summer creating a larger temperature difference between the water of the Arabian Sea and the Indian subcontinent landmass.

The temperature difference is responsible for a disparity in pressure over land and sea, creating a low pressure system over the Indian subcontinent and a high pressure system over the Arabian Sea. This difference in pressure causes winds to blow from the Southwest Arabian Sea bringing annual rainfall to the subcontinent from June to September. In the Western Arabian Sea, these winds also cause upwelling of cooler nutrient-rich water, creating ideal conditions for phytoplankton to bloom every year during summer.

Since 1997, a reduction in snow has led to wider temperature differences between the land and ocean during summer. As a consequence, sea surface winds over the Arabian Sea have strengthened leading to more intense upwelling and more widespread blooms of phytoplankton along the coasts of Somalia, Yemen and Oman.

According to Goes, while large blooms of phytoplankton can enhance fisheries, exceptionally large blooms could be detrimental to the ecosystem. Increases in phytoplankton amounts can lead to oxygen depletion in the water column and eventually to a decline in fish populations.

The Arabian Sea hosts one of the world’s largest pools of oxygen-poor water at depths between 200 and 1,000 meters (656 to 3,281 feet). Since the Arabian Sea lacks an opening to the north, the deeper waters are not well ventilated. Also when organic matter produced by phytoplankton breaks down and decomposes, more oxygen gets consumed in the process. An increase in phytoplankton could therefore cause oxygen deficiencies in the Arabian Sea to spread, leading to fish mortality.

Oxygen-depleted waters also provide the perfect environment for the growth of a specialized group of bacteria called denitrifying bacteria. These bacteria convert a nitrogen-based nutrient readily consumable by plants in seawater, called nitrate, into forms of nitrogen that most plants cannot use.

One form of nitrogen that plants cannot consume is nitrous oxide, also known as laughing gas. In the atmosphere, nitrous oxide is 310 times more potent as a greenhouse gas than carbon dioxide. Thus, as very large phytoplankton blooms deplete more oxygen from the water, the creation of nitrous oxide in the Arabian Sea could exacerbate climate change, Goes said.

Original press release: NASA Study Finds Snow Melt Causes Large Ocean Plant Blooms (NASA)