Tag Archives: Montreal Protocol

Warsaw – Day 11: Nitrous oxide 'is potent double threat'

FOR IMMEDIATE RELEASE
The Climate News Network’s Paul Brown, at the UN climate talks – the 19th Conference of the Parties of the UN Framework Convention on Climate Change – reports on a warning by scientists that nitrous oxide is both a main greenhouse gas and today’s principal destroyer of the ozone layer.

Nitrous oxide, perhaps better known as laughing gas, is produced from agriculture, industry and coal plants. It has long been known as a powerful greenhouse gas. But it is largely forgotten in climate negotiations, the UN Environment Programme (UNEP) says.

Yet emissions urgently need to be reduced, UNEP argues, because nitrous oxide (N2O) has also become the main destroyer of the ozone layer and so is a danger to humanity on two fronts.

A UNEP report, Drawing Down N2O, written by scientists from 35 organisations, shows the damage currently done by the gas and suggests ways of reducing emissions that would improve agricultural yields and save $23 billion in fertilizer costs.

The report says N2O is the third most important greenhouse gas emitted to the atmosphere by human activities. One ton of N2O has an impact equal to 300 tons of carbon dioxide, CO2.

Since the industrial revolution manmade emissions have increased the level of N2O in the atmosphere by 20%, and unless action is taken, the report says, another 5.3 million tons will be released by 2050.

The gas lasts up to 120 years in the atmosphere, where it drifts upwards to damage the ozone layer. Now that chlorofluorocarbons (CFCs) and chlorine-based chemical emissions have been reduced, N2O  is the largest single cause of ozone depletion. Unless emissions are curbed the gas could undo the work of the Montreal Protocol in reducing the size of the ozone “hole”.

No laughing matter

Achim Steiner, executive director of UNEP, said that from the viewpoint of the climate negotiations, tackling N2O emissions could be crucial in keeping the world temperature increase below the 2°C danger level agreed by governments.

“UNEP’s role is to draw the attention of this conference to the science so that politicians can act”, he said. “Although this is known as laughing gas, it is far from a laughing matter as far as its effect on the ozone layer and the climate is concerned. It has a disproportionate impact on global warming because of its warming properties and long lifetime in the atmosphere.”

The report says that emissions can be reduced by increasing the efficiency of farmers in using fertilizer and so minimizing the loss of nitrogen to the environment. Other options include reducing meat consumption, as producing meat protein causes more emissions than plant protein.

Controlling emissions from just two chemical processes that produce adipic acid and nitric acid would reduce global emissions by 5%, says the report.

Controlling forest fires and the burning of biomass and improving the combustion efficiency of stoves would also help significantly. Wastewater treatment that recycles nutrients as fertilizer would also ease the problem.

Prof Rabi Ravishankara, from the US National Oceanic and Atmospheric Administration, said: “This is the forgotten gas of both climate and ozone.  It is a natural gas, but it stayed in a steady state in the atmosphere until human beings began to interfere with the natural balance of things.

“It is a problem because it is a very good greenhouse gas and it stays so long in the atmosphere. It is an unintended release from many of our activities, but we could do much to stop this happening. That is what this report is about.” – Climate News Network

FOR IMMEDIATE RELEASE
The Climate News Network’s Paul Brown, at the UN climate talks – the 19th Conference of the Parties of the UN Framework Convention on Climate Change – reports on a warning by scientists that nitrous oxide is both a main greenhouse gas and today’s principal destroyer of the ozone layer.

Nitrous oxide, perhaps better known as laughing gas, is produced from agriculture, industry and coal plants. It has long been known as a powerful greenhouse gas. But it is largely forgotten in climate negotiations, the UN Environment Programme (UNEP) says.

Yet emissions urgently need to be reduced, UNEP argues, because nitrous oxide (N2O) has also become the main destroyer of the ozone layer and so is a danger to humanity on two fronts.

A UNEP report, Drawing Down N2O, written by scientists from 35 organisations, shows the damage currently done by the gas and suggests ways of reducing emissions that would improve agricultural yields and save $23 billion in fertilizer costs.

The report says N2O is the third most important greenhouse gas emitted to the atmosphere by human activities. One ton of N2O has an impact equal to 300 tons of carbon dioxide, CO2.

Since the industrial revolution manmade emissions have increased the level of N2O in the atmosphere by 20%, and unless action is taken, the report says, another 5.3 million tons will be released by 2050.

The gas lasts up to 120 years in the atmosphere, where it drifts upwards to damage the ozone layer. Now that chlorofluorocarbons (CFCs) and chlorine-based chemical emissions have been reduced, N2O  is the largest single cause of ozone depletion. Unless emissions are curbed the gas could undo the work of the Montreal Protocol in reducing the size of the ozone “hole”.

No laughing matter

Achim Steiner, executive director of UNEP, said that from the viewpoint of the climate negotiations, tackling N2O emissions could be crucial in keeping the world temperature increase below the 2°C danger level agreed by governments.

“UNEP’s role is to draw the attention of this conference to the science so that politicians can act”, he said. “Although this is known as laughing gas, it is far from a laughing matter as far as its effect on the ozone layer and the climate is concerned. It has a disproportionate impact on global warming because of its warming properties and long lifetime in the atmosphere.”

The report says that emissions can be reduced by increasing the efficiency of farmers in using fertilizer and so minimizing the loss of nitrogen to the environment. Other options include reducing meat consumption, as producing meat protein causes more emissions than plant protein.

Controlling emissions from just two chemical processes that produce adipic acid and nitric acid would reduce global emissions by 5%, says the report.

Controlling forest fires and the burning of biomass and improving the combustion efficiency of stoves would also help significantly. Wastewater treatment that recycles nutrients as fertilizer would also ease the problem.

Prof Rabi Ravishankara, from the US National Oceanic and Atmospheric Administration, said: “This is the forgotten gas of both climate and ozone.  It is a natural gas, but it stayed in a steady state in the atmosphere until human beings began to interfere with the natural balance of things.

“It is a problem because it is a very good greenhouse gas and it stays so long in the atmosphere. It is an unintended release from many of our activities, but we could do much to stop this happening. That is what this report is about.” – Climate News Network

Warsaw – Day 11: Nitrous oxide ‘is potent double threat’

FOR IMMEDIATE RELEASE The Climate News Network’s Paul Brown, at the UN climate talks – the 19th Conference of the Parties of the UN Framework Convention on Climate Change – reports on a warning by scientists that nitrous oxide is both a main greenhouse gas and today’s principal destroyer of the ozone layer. Nitrous oxide, perhaps better known as laughing gas, is produced from agriculture, industry and coal plants. It has long been known as a powerful greenhouse gas. But it is largely forgotten in climate negotiations, the UN Environment Programme (UNEP) says. Yet emissions urgently need to be reduced, UNEP argues, because nitrous oxide (N2O) has also become the main destroyer of the ozone layer and so is a danger to humanity on two fronts. A UNEP report, Drawing Down N2O, written by scientists from 35 organisations, shows the damage currently done by the gas and suggests ways of reducing emissions that would improve agricultural yields and save $23 billion in fertilizer costs. The report says N2O is the third most important greenhouse gas emitted to the atmosphere by human activities. One ton of N2O has an impact equal to 300 tons of carbon dioxide, CO2. Since the industrial revolution manmade emissions have increased the level of N2O in the atmosphere by 20%, and unless action is taken, the report says, another 5.3 million tons will be released by 2050. The gas lasts up to 120 years in the atmosphere, where it drifts upwards to damage the ozone layer. Now that chlorofluorocarbons (CFCs) and chlorine-based chemical emissions have been reduced, N2O  is the largest single cause of ozone depletion. Unless emissions are curbed the gas could undo the work of the Montreal Protocol in reducing the size of the ozone “hole”.

No laughing matter

Achim Steiner, executive director of UNEP, said that from the viewpoint of the climate negotiations, tackling N2O emissions could be crucial in keeping the world temperature increase below the 2°C danger level agreed by governments. “UNEP’s role is to draw the attention of this conference to the science so that politicians can act”, he said. “Although this is known as laughing gas, it is far from a laughing matter as far as its effect on the ozone layer and the climate is concerned. It has a disproportionate impact on global warming because of its warming properties and long lifetime in the atmosphere.” The report says that emissions can be reduced by increasing the efficiency of farmers in using fertilizer and so minimizing the loss of nitrogen to the environment. Other options include reducing meat consumption, as producing meat protein causes more emissions than plant protein. Controlling emissions from just two chemical processes that produce adipic acid and nitric acid would reduce global emissions by 5%, says the report. Controlling forest fires and the burning of biomass and improving the combustion efficiency of stoves would also help significantly. Wastewater treatment that recycles nutrients as fertilizer would also ease the problem. Prof Rabi Ravishankara, from the US National Oceanic and Atmospheric Administration, said: “This is the forgotten gas of both climate and ozone.  It is a natural gas, but it stayed in a steady state in the atmosphere until human beings began to interfere with the natural balance of things. “It is a problem because it is a very good greenhouse gas and it stays so long in the atmosphere. It is an unintended release from many of our activities, but we could do much to stop this happening. That is what this report is about.” – Climate News Network

FOR IMMEDIATE RELEASE The Climate News Network’s Paul Brown, at the UN climate talks – the 19th Conference of the Parties of the UN Framework Convention on Climate Change – reports on a warning by scientists that nitrous oxide is both a main greenhouse gas and today’s principal destroyer of the ozone layer. Nitrous oxide, perhaps better known as laughing gas, is produced from agriculture, industry and coal plants. It has long been known as a powerful greenhouse gas. But it is largely forgotten in climate negotiations, the UN Environment Programme (UNEP) says. Yet emissions urgently need to be reduced, UNEP argues, because nitrous oxide (N2O) has also become the main destroyer of the ozone layer and so is a danger to humanity on two fronts. A UNEP report, Drawing Down N2O, written by scientists from 35 organisations, shows the damage currently done by the gas and suggests ways of reducing emissions that would improve agricultural yields and save $23 billion in fertilizer costs. The report says N2O is the third most important greenhouse gas emitted to the atmosphere by human activities. One ton of N2O has an impact equal to 300 tons of carbon dioxide, CO2. Since the industrial revolution manmade emissions have increased the level of N2O in the atmosphere by 20%, and unless action is taken, the report says, another 5.3 million tons will be released by 2050. The gas lasts up to 120 years in the atmosphere, where it drifts upwards to damage the ozone layer. Now that chlorofluorocarbons (CFCs) and chlorine-based chemical emissions have been reduced, N2O  is the largest single cause of ozone depletion. Unless emissions are curbed the gas could undo the work of the Montreal Protocol in reducing the size of the ozone “hole”.

No laughing matter

Achim Steiner, executive director of UNEP, said that from the viewpoint of the climate negotiations, tackling N2O emissions could be crucial in keeping the world temperature increase below the 2°C danger level agreed by governments. “UNEP’s role is to draw the attention of this conference to the science so that politicians can act”, he said. “Although this is known as laughing gas, it is far from a laughing matter as far as its effect on the ozone layer and the climate is concerned. It has a disproportionate impact on global warming because of its warming properties and long lifetime in the atmosphere.” The report says that emissions can be reduced by increasing the efficiency of farmers in using fertilizer and so minimizing the loss of nitrogen to the environment. Other options include reducing meat consumption, as producing meat protein causes more emissions than plant protein. Controlling emissions from just two chemical processes that produce adipic acid and nitric acid would reduce global emissions by 5%, says the report. Controlling forest fires and the burning of biomass and improving the combustion efficiency of stoves would also help significantly. Wastewater treatment that recycles nutrients as fertilizer would also ease the problem. Prof Rabi Ravishankara, from the US National Oceanic and Atmospheric Administration, said: “This is the forgotten gas of both climate and ozone.  It is a natural gas, but it stayed in a steady state in the atmosphere until human beings began to interfere with the natural balance of things. “It is a problem because it is a very good greenhouse gas and it stays so long in the atmosphere. It is an unintended release from many of our activities, but we could do much to stop this happening. That is what this report is about.” – Climate News Network

Saving ozone may slow warming rate

EMBARGOED until 1800 GMT on Sunday 10 November What appears to be a slowdown in the rate of atmospheric warming this century may have a simple explanation, Mexican scientists say. It could be the consequence of protecting the ozone layer. LONDON, 10 November – Scientists who looked at the whole history of climate in the 20th century have come up with a new possible explanation for the apparent slowdown in global warming. It is because, they say, of the Montreal Protocol that banned chlorofluorocarbons, also known as CFCs, and saved the ozone layer. The ozone layer was the second great atmospheric crisis of the late 20th century (the first involved the urban smog and acid rain that triggered clean air legislation in Europe and the US). CFCs were the safe, enduring gases used as refrigerants: their only problem was that – once they reached the stratosphere – they unexpectedly began to destroy the ozone layer that screens out harmful ultraviolet light. Within four years of the dramatic discovery of a huge “hole” in the ozone layer over the Antarctic, these gases were phased out, in a rare act of international agreement, by the 1989 Montreal Protocol. But CFCs had a second unexpected property. They were greenhouse gases of unusual potency: molecule for molecule, one of them was rated at more than 17,000 times more effective at trapping infra-red radiation than carbon dioxide. CFCs were released only in comparatively tiny quantities, but they were calculated to account for up to 24% of global warming. Francisco Estrada of the National Autonomous University of Mexico and colleagues report in Nature Geoscience that they spotted the signal of the missing CFCs when they used statistical analysis to examine average temperature records in the two hemispheres from 1880 to 2010.

Tentative results, clear pattern

Exercises such as these are not simple: the scientists had to find a way of eliminating natural cycles that keep the weather in a permanent pattern of change, and identify long-term trends that could be identified as evidence of human activity. In the first place, for a mix of reasons, rates of change in the two hemispheres are out of step; in the second place there are natural cycles linked to ocean and atmospheric circulation such as the Atlantic Multidecadal Oscillation that are associated with extended periods of warming and cooling; in the third place things like greenhouse gas emissions are tied into cycles of economic growth, and affected again in many cases by legislation, perhaps to reduce the aerosols that make citizens cough and splutter, but that also block sunlight and have a mild cooling effect. And to get the results that they did, the researchers had to use advanced statistical methods (for example, they say, the “Perron-Yabu testing procedure, valid with integrated or stationary noise”) that would baffle most of the human race. So like all research results, the findings are tentative and published to provoke more research. But even so, the graphs in Nature Geoscience show a pattern of human influence in global average temperatures. In the last century, the planet warmed overall by 0.8°C. In the trend discernible in the sometimes dramatic oscillations of temperature, there is evidence of a slowdown in this warming during two world wars, and the Great Depression of the 1930s, when world trade came to a standstill, factories closed everywhere, and chimneys stopped smoking. The authors see a pronounced rise in both greenhouse gas emissions and in global temperatures in the 1960s – the start of sustained global warming. But they also see a distinct slowdown that begins in the 1990s in response to the Montreal Protocol, which began the phase-out of the CFCs and the slow restoration of the ozone screen.

Slowdown caused by humans

The Montreal Protocol is not the only possible explanation for the apparent slowdown. There is also evidence that at least one sector of deep ocean is warming 15 times faster than at any time in the last 10,000 years, which suggests that ocean circulation may be carrying away the heat that meteorologists expected to record in the atmosphere. Two scientists in October proposed that the slowdown in the rate of global warming could possibly be explained by a much longer-term natural cycle that nobody had yet identified: a climate signal could propagate across the northern hemisphere in a self-organising way, just as the so-called “stadium wave” propagates around a sports arena as excited spectators stand and sit down again. They say in Climate Dynamics that such a phenomenon could be linked to a brake-and-accelerator pattern of influence of northern sea ice on atmosphere and ocean circulation. If this pattern exists, it would explain why climate modellers had not predicted the present lull or slowdown in global warming. But the wave itself would have nothing to do with global warming, the two authors say. It would just offer a new perspective for climate science. The Nature Geoscience paper, however, does once again confirm the link between average temperatures and greenhouse gas emissions. “Paradoxically the recent decrease in warming, presented by global warming sceptics as proof that humankind cannot affect the climate system, is shown to have a direct human origin,” the authors conclude.- Climate News Network

EMBARGOED until 1800 GMT on Sunday 10 November What appears to be a slowdown in the rate of atmospheric warming this century may have a simple explanation, Mexican scientists say. It could be the consequence of protecting the ozone layer. LONDON, 10 November – Scientists who looked at the whole history of climate in the 20th century have come up with a new possible explanation for the apparent slowdown in global warming. It is because, they say, of the Montreal Protocol that banned chlorofluorocarbons, also known as CFCs, and saved the ozone layer. The ozone layer was the second great atmospheric crisis of the late 20th century (the first involved the urban smog and acid rain that triggered clean air legislation in Europe and the US). CFCs were the safe, enduring gases used as refrigerants: their only problem was that – once they reached the stratosphere – they unexpectedly began to destroy the ozone layer that screens out harmful ultraviolet light. Within four years of the dramatic discovery of a huge “hole” in the ozone layer over the Antarctic, these gases were phased out, in a rare act of international agreement, by the 1989 Montreal Protocol. But CFCs had a second unexpected property. They were greenhouse gases of unusual potency: molecule for molecule, one of them was rated at more than 17,000 times more effective at trapping infra-red radiation than carbon dioxide. CFCs were released only in comparatively tiny quantities, but they were calculated to account for up to 24% of global warming. Francisco Estrada of the National Autonomous University of Mexico and colleagues report in Nature Geoscience that they spotted the signal of the missing CFCs when they used statistical analysis to examine average temperature records in the two hemispheres from 1880 to 2010.

Tentative results, clear pattern

Exercises such as these are not simple: the scientists had to find a way of eliminating natural cycles that keep the weather in a permanent pattern of change, and identify long-term trends that could be identified as evidence of human activity. In the first place, for a mix of reasons, rates of change in the two hemispheres are out of step; in the second place there are natural cycles linked to ocean and atmospheric circulation such as the Atlantic Multidecadal Oscillation that are associated with extended periods of warming and cooling; in the third place things like greenhouse gas emissions are tied into cycles of economic growth, and affected again in many cases by legislation, perhaps to reduce the aerosols that make citizens cough and splutter, but that also block sunlight and have a mild cooling effect. And to get the results that they did, the researchers had to use advanced statistical methods (for example, they say, the “Perron-Yabu testing procedure, valid with integrated or stationary noise”) that would baffle most of the human race. So like all research results, the findings are tentative and published to provoke more research. But even so, the graphs in Nature Geoscience show a pattern of human influence in global average temperatures. In the last century, the planet warmed overall by 0.8°C. In the trend discernible in the sometimes dramatic oscillations of temperature, there is evidence of a slowdown in this warming during two world wars, and the Great Depression of the 1930s, when world trade came to a standstill, factories closed everywhere, and chimneys stopped smoking. The authors see a pronounced rise in both greenhouse gas emissions and in global temperatures in the 1960s – the start of sustained global warming. But they also see a distinct slowdown that begins in the 1990s in response to the Montreal Protocol, which began the phase-out of the CFCs and the slow restoration of the ozone screen.

Slowdown caused by humans

The Montreal Protocol is not the only possible explanation for the apparent slowdown. There is also evidence that at least one sector of deep ocean is warming 15 times faster than at any time in the last 10,000 years, which suggests that ocean circulation may be carrying away the heat that meteorologists expected to record in the atmosphere. Two scientists in October proposed that the slowdown in the rate of global warming could possibly be explained by a much longer-term natural cycle that nobody had yet identified: a climate signal could propagate across the northern hemisphere in a self-organising way, just as the so-called “stadium wave” propagates around a sports arena as excited spectators stand and sit down again. They say in Climate Dynamics that such a phenomenon could be linked to a brake-and-accelerator pattern of influence of northern sea ice on atmosphere and ocean circulation. If this pattern exists, it would explain why climate modellers had not predicted the present lull or slowdown in global warming. But the wave itself would have nothing to do with global warming, the two authors say. It would just offer a new perspective for climate science. The Nature Geoscience paper, however, does once again confirm the link between average temperatures and greenhouse gas emissions. “Paradoxically the recent decrease in warming, presented by global warming sceptics as proof that humankind cannot affect the climate system, is shown to have a direct human origin,” the authors conclude.- Climate News Network