Will anyone follow this route to low emission, low cost farming?

Ammonia fertiliser plays a crucial role in producing the food we need. Image credit: Allen (roadsidepictures) used via Flickr Creative Commons licence.

Ammonia fertiliser plays a crucial role in producing the food we need. Image credit: Allen (roadsidepictures) used via Flickr Creative Commons licence.

Can we make sure we make the most of the promising ideas people come up with to restrain and adapt to the changes we’re making to the climate? I’ve been considering this question thanks to a recent invention seeking to help cut increasing greenhouse gas emissions that arise from feeding the world’s growing population. Stuart Licht’s team at George Washington University in Washington, DC, has worked out how to make a key component of fertiliser – ammonia – that could eliminate emissions and minimise cost. In fact it’s an extension of a method that Stuart told me can also produce zero carbon cement, iron, bleach, magnesium, and capture CO2 directly from the atmosphere. So when will we see this amazing approach in use? I can’t tell you that – because Stuart has no plans to commercialise it.

I became aware of the new ammonia production system when Chemistry World asked me to cover it for them. Ammonia is a simple molecule, comprising only two elements, hydrogen and nitrogen. Humans have been using it in fertiliser since at least the early 19th century, when it was mined, both in mineral form and as bird guano, for delivery to farmers. That was necessary because although nitrogen is hugely abundant – it makes up four-fifths of Earth’s atmosphere – it’s equally as unreactive. Chemists often replace the air above the reactions in their flasks with pure nitrogen when they’re worried that oxygen will affect their results. That stability meant synthetic ammonia was at first elusive.

But in the early 20th century Fritz Haber and Carl Bosch found a way to overcome nitrogen’s reluctance to react. They could take nitrogen from the air, and bring it together with hydrogen gas in the presence of an osmium catalyst at very high pressures and temperatures. During the First World War ammonia’s other main application – as a basis for explosives – saw that ramped up to industrial scale. The Haber-Bosch process has provided fertilisers that have been crucial in feeding Earth’s growing population since then. But it comes with a downside: it requires huge amounts of energy – 2% of the entire world’s consumption – whose generation usually releases the greenhouse gas CO2. Read the rest of this entry »

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The climate challenges that my morning toast poses

Britain's wheatfields could become even more productive as the world warms - but that will have implications for further greenhouse gas emissions and fairness to countries less well positioned. Image credit: Tim Gage used via Flickr Creative Commons license

Britain’s wheatfields could become even more productive as the world warms – but that will have implications for further greenhouse gas emissions and fairness to countries less well positioned. Image credit: Tim Gage used via Flickr Creative Commons license

It may seem that nothing could be simpler than toast, but next time I see a slice pop up I’ll also see an emblem of the world’s future. That’s thanks to a UK study exploring the problems surrounding growing enough wheat for flour and other foods as the world warms and has ever more people in it. The issue is especially tangled, Mirjam Röder and her University of Manchester teammates show, as adapting farming for the future will likely increase greenhouse gas emissions, driving further warming. “Climate change and food security are two issues which can’t be decoupled,” Mirjam told me. “The same applies for mitigation and adaptation.”

Mirjam is part of the “Climate change mitigation and adaptation in the UK food system” project, led by Alice Bows-Larkin and backed by Manchester’s Sustainable Consumption Institute. One concern the project reflects is that without adaptation farming will probably be the industry worst hit by climate change, with worldwide productivity falling as temperatures rise. Meanwhile, farming also releases about one-tenth of the greenhouse gases we humans emit overall. “These are largely emissions other than CO2, such as nitrous oxide and methane, mainly occurring from natural processes,” Mirjam said. “They are much harder to reduce and control. Then of course global society is challenged by increasing global food demand. So we face a triad of challenges in the food system: we need to reduce emissions, while food demand is increasing and the sector is impacted by climate change.”

Alice and Mirjam’s team looked at wheat because it makes up almost a third of all cereals grown in the world. “Global wheat demand is projected to increase by about 30% by 2050,” Mirjam. “If we don’t find methods to reduce them, total emissions from producing more wheat will rise.” As well as gases released directly by bacteria and other soil microorganisms, emissions from wheat farming arise from the energy needed to produce nitrogen fertiliser. Whether growing more wheat or dealing with rising temperatures, farmers will need more fertiliser, driving more emissions and therefore further warming. Read the rest of this entry »

Stark conclusions seek to empower young to sue for climate justice

Jim Hansen (bottom left) and his family. For their benefit, and for the next generation as a whole, he is pushing for more urgent action on global warming. Credit: James Hansen

Jim Hansen (bottom left) and his family. For their benefit, and for the next generation as a whole, he is pushing for more urgent action on global warming. Credit: JimHansen

Even limiting human-made global climate warming to 2°C above preindustrial temperatures would subject young people, future generations and nature to irreparable harm, leading scientists said on Tuesday. The team led by pioneering climate researcher Jim Hansen, now at Columbia University in New York, calls aiming for this internationally-recognised threshold ‘foolhardy’. In a paper published in PLOS ONE, they outline a case for aiming for 1°C that supports efforts to sue the US government for not doing enough.

“Governments are blatantly failing to do their job,” Jim told me. “They know that human-caused climate change is beginning and poses a huge risk to young people and future generations, and they understand that we must phase out fossil fuel emissions. Yet they go right ahead encouraging companies to go after every fossil fuel that can be found!”

As one of the first climate modellers, Jim has long warned about the greenhouse effect caused by the CO2 we emit from burning fossil fuels. On a sweltering June 23, 1988, he famously testified to the Energy and Natural Resources Committee of the US Senate on the dangers of global warming. “It’s time to stop waffling so much and say that the evidence is pretty strong that the greenhouse effect is here,” he told reporters at the time.

Yet Jim remains frustrated at the slow pace of action, and regularly voices it. In 2006 Mary Wood from the University of Oregon Law School saw one of his articles in the New York Review of Books and contacted him. Her work inspired the formation of a team of lawyers who are suing the US federal government, highlighting the principle that US citizens, young and old, have ‘equal protection of the laws’. “I agreed specifically to write a paper that would provide the scientific basis for legal actions against governments for not doing their job of protecting the rights of young people,” Jim recalled. Read the rest of this entry »

Speeding poor countries’ progress could halve farming emission growth

Improving agricultural productivity - particularly without increasing fertiliser use - could help cut greenhouse gas emissions from agriculture. Credit: IIASA

Improving agricultural productivity – particularly without increasing fertiliser use – could help cut greenhouse gas emissions from agriculture. Credit: IIASA

If the world’s poorer countries progress faster towards farming like richer ones the improved food availability could help fight climate change. That’s according to Austrian and Australian scientists who say that they have looked at climate change’s links to both animal and crop farming in the most depth yet.

Hugo Valin from the International Institute for Applied Systems Analysis (IIASA) in Laxenburg, Austria, and his colleagues studied cutting the gaps between farming output in rich and poor countries. They say halving this ‘yield gap’ for crops, and reducing it by a quarter for animals, could halve the increase in worldwide greenhouse gas emissions from farming between 2000 and 2050. But they have also found that improved farming methods could raise how much food people eat, meaning that emission reductions aren’t as much as they would be otherwise.

“The widespread idea is that intensifying crop farming is beneficial to the environment because it spares land,” Hugo told me. “We show that it is more complex than this. Intensification also stimulates consumption because it allows farmers to supply more food at affordable prices.”

Farming produces about a third of all ‘man-made’ greenhouse gas emissions, though a lot of them are actually from farm animals’ belches and farts and manure. The rest come from chemical reactions of fertiliser used on crops in soil, and also gases released from soil, plants and trees when forests are converted into farmland. Four-fifths of these emissions happen in developing countries. The world’s population is set to grow from around 7 billion people today to between 8.3 and 10.9 billion by 2050. We need more food for those extra people, which will add to the greenhouse gases farming puts into the air each year. Read the rest of this entry »

N2O cuts are no laughing matter

Eric Davidson, executive director at the Woods Hole Research Center in Falmouth, Massachusetts. Credit: Woods Hole Research Center

Eric Davidson, executive director at the Woods Hole Research Center in Falmouth, Massachusetts. Credit: Woods Hole Research Center

Also known as laughing gas, nitrous oxide (N2O) is a powerful greenhouse gas, and bringing its release under control will need the world to make very serious changes. That’s what Eric Davidson, executive director at the Woods Hole Research Center in Falmouth, Massachusetts, has found by looking at likely future N2O emissions.

Improvements in farming, industry and transportation could help reduce levels of the gas from what they might become. So too could the hard-to-swallow suggestion for many that people in the world’s richest countries halve the amount of meat they eat. But to meet the hardest target scenario to be used in an important climate report scientists are working on, we need to do all of these, Eric says. “Mitigating N2O emissions will be a huge challenge, and I’ve outlined the scope of the magnitude of change necessary,” he told Simple Climate. “They are not outside the realm of possibility, although they will be very challenging.”

In 2008, the UN Intergovernmental Panel on Climate Change (IPCC) agreed it would produce its fifth assessment report looking at global warming in detail by October 2014. To try and predict what will happen in the future, the scientists involved have drawn up four “representative concentration pathway” (RCP) scenarios that humanity could follow. These are based on a range of values for how much the atmosphere would be heating up in 2100. But there has been little work so far to see what will need to happen to reach the greenhouse gas levels these scenarios imply. Read the rest of this entry »

Climate controls must cover gases other than CO2

Agriculture is one of the main sources for the greenhouse gas nitrous oxide (N2O) which results from the use of fertilisers. Credit: André Künzelmann/UFZ

Agriculture is one of the main sources for the greenhouse gas nitrous oxide (N2O) which results from the use of fertilisers. Credit: André Künzelmann/UFZ

Cutting emissions of other greenhouse gases would slam the brakes on short-term climate change faster than controlling CO2 alone. But rather than offering an easy way out, warns Jim Butler, director of the Global Monitoring Division at the US National Oceanic and Atmospheric Administration (NOAA), they present both an opportunity and a challenge. “Addressing them can help us see earlier results than we would see with CO2, which poses a problem today but a much bigger one in the future,” he told Simple Climate. “CO2 must be addressed, but ignoring these other gases too could take us to places where we don’t want to go.”

Butler’s division has tracked the levels of different gases in the atmosphere for decades. Among them he says, CO2 rightfully gains most attention. That’s because it traps so much of the sun’s energy, it currently accounts for almost two-thirds of the warming power known as “climate forcing”. “It is responsible for well over 80 per cent of the increase in climate forcing from long-lived gases each year,” Butler said. “It is also very long lived, with around one-fifth of what is emitted hanging around for at least 1,000 years.” Yet as burning oil, natural gas and coal, which produces CO2, propels modern life, cutting the amount we use enough will take some time. “In the meantime there are other gases that could and probably should receive attention,” Butler underlined.

Stephen Montzka of NOAA, along with colleagues Butler and Ed Dlugokencky, looked at exactly how these gases have been affecting climate in top scientific journal Nature this week. Monitoring and evaluating these gases helps show how humans are affecting their levels in the atmosphere. It also serves as a check on the results of claimed emissions. Unfortunately, the amount countries say they produce and levels recorded at observatories across the world disagree. However, Butler noted that no approach is perfect, and that at least comparing the two gave them some idea how far out they were. “The beauty of comparing the two is that each relies on completely different measurements, procedures and assumptions,” he said. Read the rest of this entry »

Effluent entering streams also soils the atmosphere

The Corralles drainage ditch in Albuquerque, New Mexico, was one of 72 sites used to study nitrous oxide emissions from rivers and streams. Credit: Chelsea Crenshaw

The Corralles drainage ditch in Albuquerque, New Mexico, was one of 72 sites used to study nitrous oxide emissions from rivers and streams. Credit: Chelsea Crenshaw

Across the world, humans are causing rivers and streams to release the potent greenhouse gas nitrous oxide at levels three times higher than used in climate change predictions. Known as laughing gas when used as an anaesthetic, nitrous oxide is also a greenhouse gas over 300 times more powerful than CO2 on a per-molecule basis. How much of this gas comes from streams and rivers wasn’t previously well known, and scenarios predicting future climate change were based on estimates. Now, writing in the journal Proceedings of the National Academy of Sciences of the United States of America on Monday, a large team of US scientists has filled this knowledge gap.

Humans cause chemicals with high nitrogen contents from sources like fertilizers and sewage to enter water bodies as dissolved inorganic nitrogen (DIN). Microbes help break the DIN down, first by converting it into nitrates, and then converting these nitrate chemicals into nitrous oxide and nitrogen gas in a process called denitrification. Only a tiny amount of nitrous oxide is produced during denitrification in comparison to nitrogen gas. Previously, climate change models produced by the Intergovernmental Panel on Climate Change (IPCC) assumed that just 1 part of nitrous oxide is produced from 400 parts of DIN on average worldwide. Read the rest of this entry »