Is the Scale of Climate Change overstated?

March 28, 2010 · Filed Under news · Comment 

Many people say:

“The scale of the negative effects of climate change is often overstated and there is no need for urgent action.”

What does the science – and the Royal Society – say?

Under one of its mid range estimates, the Inter Governmental Panel on Climate Change (IPCC) – the world’s leading authority on climate change – has projected a global average temperature increase this century of two to three degrees centigrade. This would mean that the earth will experience a larger climate change than it has experienced for at least 10,000 years. The impact and pace of this change would be difficult for many people and the ecosystems to adapt to.

However, the IPCC has pointed out that as climate change progresses it is likely that negative effects wold begin to dominate almost everywhere. Increasing temperatures are likely, for example to increase the frequency and severity of weather events such as heatwaves, storms and flooding.

Furthermore there are real concerns that, in the longterm, rising levels of greenhouse gases in the atmosphere could set in motion large scale and potentially abrupt changes in our planet’s natural systems and some of these could be irreversible. Increasing temperatures could, for example, lead to the melting of large ice sheets with major consequences for low lying areas throughout the world.

And the impact of climate change will fall disproportionately upon developing countries and the poor – those who could can least afford to adapt. Thus a changing climate will exacerbate inequalities in, for example, health and access to adequate food and water.

Number of Sunspots effect Earth’s Temperature?

March 24, 2010 · Filed Under news · Comment 

People want to believe climate change isn’t happening.  One common argument used used is: 

It’s all to do with the sun – for example, there is a strong link between the increased temperature on earth and the number of sunspots on the sun.

But what does the science – and the Royal Society –  say?

 Change in solar activity is one of the many factors that influence the climate but cannot, on its own, account for the change in global average temperature that we have seen in the 21st century.

 Changes in the sun’s activity influence the earth’s climate through small but significant variations in its intensity. When it is a more “active” phase – as indicated by a greater number of sunspots on its surface – it emits more light and heat. While there is evidence of a link between solar activity and some of the warming in the early 20th century, measurements from satellites show that there has been very little change in underlying solar activity in the last 30 years. There is even evidence of a detectable decline – and so this cannot account for the recent rises we have seen in global temperatures. The magnitude and pattern of changes to temperatures can only be understood by taking all of the relevant factors – both natural and human – into account. For example, major volcanic eruptions produce a cooling effect because they blast ash and other particles into the atmosphere where they persist for a few years and reduce the amount of the sun’s energy that reaches the earth’s surface. Also, burning fossil fuels produces particles called sulphate aerosols which tend to cool the climate in the same way. Over the first part of the 20th century higher levels of solar activity combined with increases in human generated carbon dioxide to raise temperatures. Between 1940 and 1970 the carbon dioxide effect was probably offset by increasing amounts of sulphate aerosols in the atmosphere, and a slight downturn in solar activity, as well as enhanced volcanic activity.

During this period global temperatures dropped. However, in the latter part of the 20th century temperatures rose well above the levels of the 1940s. Strong measures taken to reduce sulphate pollution in some regions of the world meant that industrial aerosols began to provide less compensation for an increasing warming caused by carbon dioxide. The rising temperature during this period has been partly abated by occasional volcanic eruptions.

Is Climate Change affected by Cosmic Rays?

March 11, 2010 · Filed Under news · Comment 

Many people want to believe climate change isn’t happening and use arguments such as:

“The climate is actually affected by cosmic rays.”

 But what  does the science – and the Royal Society – say?

Cosmic rays are fast moving particles which come from space, and release electric charge in the atmosphere. Any effect that cosmic rays could have on the climate is not yet very well understood, but if there is one, it is likely to be small.

Experiments done in a laboratory hint that cosmic rays could play a role in the development of tiny particles that could in turn play a part in the formation of clouds. If this happens in the same way in the atmosphere – which isn’t proven – it might lead to more clouds, which generally have a cooling effect by reflecting the sun’s rays back into space. Whether the whole chain of processes actually occurs in the atmosphere is speculative, but some of the individual steps are plausible.

It has been proposed that this process would act to enhance the influences of the sun on the climate. We know that when the sun is more active it’s magnetic field is stronger and this deflects cosmic rays away from the earth. So the argument is that a more active sun would lead to fewer cosmic rays reaching the earth, resulting in fewer clouds and therefore a warmer earth.

However, observations of clouds and galactic cosmic rays show that, at most, the possible link between cosmic rays and clouds only produces a small effect. Even if cosmic rays were shown to have a more substantial impact, the level of solar activity has changed to little over the last few decades the process could not explain the recent rises in temperature that we have seen.

Climate Change Debate – the Scientific Evidence

February 15, 2010 · Filed Under climate change · 1 Comment 

The severity and speed of man-made climate change is one of the key factors which will determine the amount of food that can be produced in the future. Most of us desperately wish it wasn’t happening and perhaps that explains why people are quick to believe anything coming from the sceptics. The East Anglia email scandal is an example of something fairly insignificant that is used to feed scepticism in the population, most of whom have not looked closely at the evidence or science.

I have heard people say that they would like to see the arguments explained by experts in an easy to understand way.

It’s great therefore that The Royal Society – as the UK’s national academy of science – has responded to eight key misleading arguments by setting out where the weight of scientific evidence lies.

We at Peak Food will show abbreviated versions of each of these arguments.

MISLEADING ARGUMENT 1

The Earth’s climate is always changing and this is nothing to do with humans. Even before the industrial revolution, when humans began pumping carbon dioxide into the atmosphere on a large scale, the earth experienced warmer periods.

WHAT DOES THE SCIENCE SAY?

The world has experienced warmer or colder periods in the past without any interference from humans. The ice ages are well-known examples of global changes to the climate. There have also been regional changes such as periods known as the ‘Medieval Warm Period’, when less sea ice and larger areas of cultivated land were reported in Iceland.

However, in contrast to these climate phases, the increase of three-quarters of a degree centigrade in average global temperatures over the last century is larger than can be accounted for by natural factors alone.

The Earth’s climate is complex and influenced by many things- particularly changes in the Earth’s orbit in relation to the Sun, which has driven the cycle of ice ages in the past. Volcanic eruptions and variations in the energy being emitted from the Sun have also had an effect. But even taking these factors into account, we cannot explain the temperature rises that we have seen over the last 100 years both on land and in the oceans- for example ,eleven of the last twelve years from 1995, have been the hottest years since records started in 1850.

So what is causing this increase in average global temperature? The natural greenhouse effect keeps the Earth around 30c warmer than it would otherwise be and, without it, the Earth would be extremely cold.

The ability of carbon dioxide and other greenhouse gases to act like a blanket and

trap heat has been understood for nearly 200 years and is regarded as firmly established science.

Any increase in the levels of greenhouse gases in the atmosphere mean that more heat is trapped and global temperatures increase-an effect known as ‘global warming’. We know from looking at gases found trapped in cores of polar ice that the levels of carbon dioxide in the atmosphere are now 35% greater than they have been for at least the last 650,000 years. The increase in global temperature is consistent with what science tells us we should expect when the levels of carbon dioxide and other greenhouse gases in the atmosphere increase in the way that they have.

It is alleged that the increased level of carbon dioxide in the atmosphere is due to emissions from volcanoes, but these account for less than one per cent of the emissions due to human activities.

TOTAL Oil Boss gives Peak Oil Warning

January 19, 2010 · Filed Under climate change · 2 Comments 

In the last few years there have been a series of remarkable u-turns from the world’s top oil companies. Not long ago they were saying that man-made climate change was a myth and funding scientists who were prepared to agree with that. Now, however, they all say that climate change is taking place and that greenhouse gas emissions are at least partly responsible. Indeed, they are all spending millions to prove their green credentials by starting projects that will reduce emissions to some extent.

Peak Oil and Peak Food

Peak Oil and Peak Food

 

Peak Oil is another matter. Until now the message coming from the oil companies is that Peak Oil – the time when a peak in production is reached, followed by a decline in production in the face of increasing demand, causing severe shortages – is many decades in to the future. Recently though there are indications that at least one company has changed its mind.

In this week’s Time magazine, Christophe de Boisseson, CEO of the French oil giant Total, speaks openly about the nightmare scenario oil shortages that most energy firms prefer to avoid or deny. De Margerie says the possible effects on the world economy of dwindling oil supplies are so great that, “I am not prepared to shut my mouth.” Shortly after taking over at Total he jolted executives at a London conference by stating that the industry would be unlikely to produce more than 100 million barrels a day, far below the 120 million or so the International Energy Agency estimates the world could produce by 2030, and which will be needed for Asia’s galloping growth. De Margerie now says 90 million barrel a day is “optimistic.”

This is worrying for the health of the world economy, but for the future of food production it is devastating. Western agriculture is totally dependent on oil and the rest of the world is rapidly becoming so.  It is expected that food production will need to double in the next 40 years as the population continues to rise and as more people demand a better diet. To increase food production using modern methods requires a corresponding increase in fossil energy inputs. A serious shortage would cause the farming industry to collapse.

The truth about our situation is so unpalatable that most people will prefer to not believe it, but it must be said. The carrying capacity of the Earth has been temporarily increased by the massive use of finite resources. When these resources become depleted, the Earth’s carrying capacity and therefore its population will be reduced – in other words mass starvation and we in the West are the most vulnerable.

Next Page »