Are wind turbines really as green as we think they are?

At the beginning of last week I wrote a post in response to an article I found on the National Geographic website that discussed how green our attempts to utilise renewable energy sources really are. Within this post I used wind farms as an example to demonstrate how we have to use many rare earth metals and other finite resources to build the equipment we require to capture renewable energy. Talking specifically about wind turbines, neodymium is vital in the production of the magnets used as the stronger the magnets the more efficient the turbines can be (around 4,400lb are needed per turbine). It was estimated that we would need to quintuple the world’s production of this rare earth metal to meet the demand. Currently, in the UK, we have 3,153 wind turbines which have a maximum capacity of 5,203 megawatts and at this level of development it is estimated that they will supply 4.6% of the energy we use in 2011. This percentage is likely to only increase as planning permission is being granted to build more wind farms – especially in Scotland. For example in December planning permission was given to build 33 turbines on the hills north of the upper Findhorn valley.  Many people, however, are still against the development of wind farms as, although they provide ‘green’ energy, they have many environmental impacts of their own. Most people oppose them because they aren’t the most picturesque objects and can spoil the previously untouched landscape. Also it is not just the turbines themselves that alter the surrounding environment. At Dunmaglass, in Scotland, a new network of roads 20 miles long has to be built so that access to the turbines is improved so that they can be serviced. Also around 1,500 tons of concrete foundations are required to provide stability to the turbines and to prevent them from falling over in strong winds. All of this adds to the negative impact that they can have on the environment and this is all before mentioning the fact that many peat moors have to be drained to put up a turbine and peat bogs naturally trap large quantities of carbon and the impact they are believed to have on birds. However wind farms are still a popular choice of renewable energy source due to the amount of coastline we have and because it is possibly one of the most developed forms of renewable energy. Before I read  an article this weekend I personally believed that wind turbines were quite a good way of utilising renewable energy sources and that even though they have their downsides surely we have to make some aesthetical sacrifices to increase the amount of renewable energy we capture. Also is a turbine really that different to a pylon? However this was all before I was aware of the impact that our attempts, as a country, to boost our environmental credentials are having elsewhere in the world.

The growing pressure put on countries to develop their renewable energy sources has increased the demand for the production of materials, like neodymium, and the speed at which this has happened has led to these materials being produced in an unsustainable way. Rare earth metals are crucial for the building of turbines and 90% of the world’s legal reserves of rare earth metals are found in Mongolia. Much of the world’s supply of neodymium comes from here and although this has allowed other countries to improve their environmental credentials; this industry has had huge negative environmental impact in China. The article I read explained how in Baotou “lies a five-mile wide ‘tailing’ lake. It has killed farmland for miles around, made thousands of people ill and put one of China’s key waterways in jeopardy”. This lake is the dumping ground for seven million tons a year of mined rare earth after it has been doused in acid and chemicals and processed through red-hot furnaces to extract its components. This is considered to be the deadly and sinister side effect of the massively profitable rare-earths industry that the ‘green’ companies profiting from the demand for wind turbines would prefer you knew nothing about and many believe that this giant, secret toxic dump is only going to be made bigger by every wind turbine we build. Like discussed in a previous blog providing clean water to the many people in China is already an issue and this is being made worse by the radioactive waste that is polluting water supplies like those in Baotou. Mr Su, a local farmer, explained how “Anything we planted just withered, then our animals started to sicken and die.” It was not only the animals that suffered but the people too. Dalahai villagers say that their teeth began to fall out, their hair turned white at unusually young ages, and they suffered from severe skin and respiratory diseases whilst children were born with soft bones and cancer rates rocketed. These claims were supported by an official study (carried out 5 years ago) which confirmed that these problems were caused by the radiation levels of the lake which were ten times higher than that of the surrounding area. This study was carried out 5 years ago and so surely the problem has only escalated since then as countries endeavour to boost their production of renewable energy. More recent studies have been carried out but their results have been kept secret and officials have refused to publicly acknowledge health risks to nearby villages – surely this just highlights the fact that the companies realise that what they are doing is wrong. The state owned Baogang Group (own most of the factories in Baotou) also claim that they invest millions of pounds a year into environmental protection but yet why is it then that the lake has to deal the discharge of 7 million tons of waste a year and that this lake (already 100ft high) grows by approximately 3ft a year. This is not the only issue linked to the production of neodymium. 

The conditions that the workers have to work in are not great either. Workers don’t have access to protective clothing except for cotton gloves and face masks even though they have to ladle molten rare earth from furnaces with temperatures of 1,000ᵒc. In the past year the price of neodymium has doubled which has provoked more factories, like this one, to develop or expand. This is going to increase the number of villagers that are exposed to these high levels of radiation within the water that they rely on for irrigation of crops and drinking water.

Despite this countries still develop wind farms from the resources that they buy from environmentally unsustainable industries like this one. So, the question is ‘How green really are the wind farms that we build in this country’? Taking all of the above examples of the negative impact wind turbines have on the environment into consideration is it really worth damaging the environment in these ways to try and produce a marginal amount of ‘green’ energy.  Despite the amount of investment that was placed on wind farms last year,  in December wind farms only produced 0.2% of the electricity that we used in the UK. This made me question whether or not wind power is the best way forward or could the money be better spent on developing other forms of renewable energy.

http://www.dailymail.co.uk/home/moslive/article-1350811/In-China-true-cost-Britains-clean-green-wind-power-experiment-Pollution-disastrous-scale.html  (This is the link to the article, ‘The Dirty Truth about Britain’s, Clean, Green Wind Power Dream’ I read and it presents the environmental impacts that wind turbines have and also breaks down how the electricity we use is produced - it is well worth a read)

At present, I don’t think I know enough about the other options to answer this question but hopefully, after all the group presentations this week, I will be able to come back to this debate and give an educated opinion on, in terms of renewable energy, what I think is the best way forward?

Student review of 'The Age of Stupid and links to a few articles related to renewable energy resources

Last week my Geography teacher watched the film The Age of Stupid and suggested that we all watched it as we would have only a limited amount of time to talk about climate change in lessons. She thought it was interesting and so I thought I would watch it and write a short review on the film from a student’s perspective.

The film is set in 2055 with a man who is living alone in a world that has been devastated by climate change. He looks back at the archives of documentaries and news reports (all of which are real) of how environmental changes have altered our lives so far and how our lifestyles have ultimately altered the environment. From the information the archives provide, he asks why didn’t we do something when we had the chance instead of ignoring the glaring signs. The film makes very clear the differences in energy uses across the world by frequently comparing the USA, UK, China, India and Africa and how our desire for resources had led to conflict and, in some regions, poverty. In terms of its relevance to what we are doing at present, the film includes two interesting case studies surrounding different energy resources. One is about the oil industry and its negative impact on the developing world with specific reference to Nigeria. The other explains the problems faced by wind farm developers who try to set up wind farms in the UK and highlights the NIMBY attitude shared by many in this country. The other case studies are also quite interesting as they delve into the reasons behind why people are reluctant to change their ways and how the changes in the environment are impacting on our daily lives. It also explains how climate change is a global issue and so attempts to reduce its impact have to be globally united ones if they are to have any significant effect. Personally I think it is well worth watching and is an easy way to spend 90 minutes if you need to learn more about this issue as the film does not really touch on any new scientific ideas but instead ties in all the basics in a watchable, but still educational, format.

I believe that most AS students have now started working on the energy presentations. Last night I was trying to do some research on my energy resource but was finding it rather tricky to do so and instead kept finding lots of useful articles on some of the other energy resources. I thought that I might include some of them on this blog encase they will be of any use to any other group. Even if they are not, they are still quite an interesting read as they provide an insight into what is happening, in terms of energy, around the world. When I was looking for articles on energy resources the first place I looked was on the National Geographic website and this is the link to their special energy section http://environment.nationalgeographic.com/environment/energy/great-energy-challenge It contains some very up to date information and is particularly good if you are looking for case studies (the majority of them are based in other countries but they still  might be useful).

 I found this article (http://www.greatenergychallengeblog.com/blog/2011/01/17/kenya-steps-into-solar-future/ ) which explains how the use of solar energy is becoming very popular in Kenya as it is cheap and means that villages don’t have to be connected to a national grid. Solar energy is the biggest form of renewable energy that is being explored in Kenya as not only is it cheap and better for the environment but there are also a lot of health risks associated with the traditionally used kerosene lamps.

Last week, India announced that they were planning to build Asia’s first commercial scale tidal power plant which is to be situated in the Gulf of Kutch and has the potential to generate many economic and environmental benefits for the region. http://www.bbc.co.uk/news/science-environment-12215065 Also, October last year, a proposal to build a tidal power plant at Pentland Firth was given the go ahead. This project will involve 400 submersed turbines which have the potential to supply the electricity needs to 400,000 homes. http://www.bbc.co.uk/news/uk-scotland-highlands-islands-11636959 After the scrapping of the Severn barrage; both of these projects provide a huge boost to the world development of tidal energy.

Geothermal energy is another type of renewable energy that is being used across the world. http://news.nationalgeographic.com/news/news/energy/2010/12/101228-geothermal-energy-pick-up-real-steam-  This form of energy currently provides Iceland with 25% of the electricity it consumes. However this source of energy is only most productive in areas which have strong volcanic activity and so cannot be utilised worldwide.

These are just a few of the articles I found (I hope they are of some use) and there are plenty more on the National Geographic website and in other places on the internet. One related article that did catch my eye was this one (http://news.nationalgeographic.com/news/energy/2011/01/110117-100-percent-renewable-energy/ ). This article discusses whether or not we can actually survive on purely ‘green’ energy in the future and the fact that to build enough power stations to enable us to do so would require the use of lots of finite resources. For example, millions of wind turbines would have to be built to allow us to become more reliant on this energy resource. To build these turbines we would need to use a lot of neodymium (used in magnets) and it is estimated that the worldwide production of this mineral would have to quintuple to supply us with the quantity that this project would require.

Current local energy issues

I learnt today, even though it was my first lesson on the new module, that to do well and understand the Energy Issues topic you need to be up to date with current issues – especially those that are local ones. It also seems vital that you are able to form your own opinions on issues like nuclear power stations and wind turbines for example. I don’t know how my fellow students felt but personally I don’t think that I know enough to form educated opinions or really know enough detail about local energy issues. So I am going to try and summarise some of the key facts about local energy issues that are likely to affect us……..

Perhaps one of the most controversial cuts, in terms of renewable energy sources, is the government’s decision to scrap the Severn Barrage. The plan was to build a 10 mile long barrage stretching from Cardiff to Weston Super-Mare. In terms of generating tidal energy at competitive prices the Severn is a perfect location as it has a tidal range of 13 metres which is considered to be the second highest in the world. Without going into too much detail, the Severn Barrage was designed to trap high tides by shutting the sluice gates at these times. The barrage was designed to have 214 turbines across its length. When the tide turned the water would be pressured out via these turbines and cause them to rotate. This would then generate the amount of electricity equivalent to 5% of the electricity we consume which is also equivalent to that produced by two nuclear power stations or eight large coal-fired power stations. As well as having the obvious environmental benefits the scheme was predicted to create around 40,000 jobs for the local people. A similar project was successfully built in France in the 1960’s. The La Rance tidal barrage is 330 metres long and produces 4% of the electricity used in Brittany. The Severn barrage would produce more energy as the tidal range of La Rance is nearly 6 metres less than that of the Severn Estuary.  However there were some disadvantages of the proposed project…….

Many people were against the Severn barrage as it is believed that it would have had negative environmental impacts that outweighed the positives. The Severn Estuary is a designated conservation area which around 85,000 birds use to migrate to. Many environmentalists believed that the building of the barrage would lead to the destruction of the mud flats which many of the migratory birds rely on. Also many felt that the barrage would impact on marine life migration patterns as some fish would not be able to return to spawn. Another environmental issue was the impact that the barrage could have on flooding as the pressure built up by the barrage during high tides could increase erosion and so some areas could experience more flooding whilst a build-up of sediment could occur in others. Flooding around the Severn Estuary is already an issue and I found this article today which discusses the views on preventing tidal flooding http://www.bbc.co.uk/news/uk-wales-12267955  There is also the issue of cost as the building of the Severn barrage was estimated to cost around £30 billion and many saw this as a too costly project. These are only some of the arguments that were used to try and stop this proposal going ahead. This audio clip includes all of these and some more in a bit more detail http://news.bbc.co.uk/today/hi/today/newsid_8645000/8645834.stm

The government decided not to support the Severn barrage in the end as they said it was not “financially viable” and instead decided to focus funding on nuclear power plants. http://www.bbc.co.uk/news/uk-wales-11568220  I can understand why many people were against this proposal but finding new sources of renewable energy is going to be hard and the Severn Estuary has the potential to supply us with a lot of ‘green’ energy. Although it would be a costly project it would also help the local economy by providing many much need jobs. In terms of the environment, I too believe that it is important to make sure that projects are environmentally sustainable and so I believe that other alternatives should have been investigated before scrapping the idea all together. However there is still a glimmer of hope for the development of tidal energy in the Severn Estuary as the government have not written off a smaller project. Unfortunately though many believe that the scrapping of the Severn barrage could have knock on effects on tidal energy in the UK as a whole and some believe that development of this energy source may not occur until 2030’s or not at all. http://www.bbc.co.uk/news/uk-11564949

Instead of pursuing tidal energy the government has decided to invest in nuclear power plants. The nearest one to us is at Hinkley Point. Hinkley A has already been decommissioned and the same will happen to Hinkley B in 2016. EDF energy, who owns the power plant, has plans to open a Hinkley C which will be bigger than the last two and will have the ability to produce 6% of the energy we consume as a country. EDF claim that the project will bring £100 million to Somerset each year during its construction and create just under 6000 jobs. After it has been constructed EDF say that it will bring in annual revenue of £40 million to the region. http://news.bbc.co.uk/local/somerset/hi/people_and_places/newsid_8797000/8797655.stm  This link is to the EDF energy website for Hinkley Point and the website contains some more information on the proposal and the site itself http://hinkleypoint.edfenergyconsultation.info/home

There is lots of opposition for this proposal; particularly in Williton, Cannington and Bridgewater as people were worried about an increase in infrastructure due to the need for accommodation for workers. Also many are worried that an increase in traffic will cause problems with congestion. The extra housing is now going to be built on brown field sites in Bridgewater instead of Williton but plans for the controversial bypass are still going ahead. Many people are simply against the idea of any nuclear energy power stations due to the risks associated with radioactive materials and the problems with disposing of the nuclear waste. Also the sustainability of nuclear energy is questionable as it relies on the use of uranium which is a critical resource. It is estimated that uranium reserves may only last for the next 30 – 60 years depending on the demand for nuclear energy and so many think that if other energy sources, especially more sustainable and renewable ones, can be exploited then they should instead of using nuclear energy.  Another problem is connecting Hinkley C to the National Grid and there is a video discussing this on the National Grid website http://www.nationalgrid.com/uk/Electricity/MajorProjects/HinkleyConnection/Documents/ (connecting Hinkley Point C – An overview)

On the other hand, some believe that the benefits of using nuclear energy outweigh the disadvantages. Talking specifically about Hinkley Point EDF energy believe that Somerset, as a region, will benefit from Hinkley C. This link is to a section of their websites which outlines what they think are the benefits of this proposal. http://hinkleypoint.edfenergyconsultation.info/key-benefits   This is a link to a very recent development surrounding the Hinkley C project as EDF energy has recently placed a lot of investment into an energy skills training scheme at Bridgewater College and this is one of the many things that EDF energy are doing to try and ensure that any development in nuclear energy at Hinkley Point will benefit the local people http://hinkleypoint.edfenergyconsultation.info/newsroom-faqs/press-releases/959

Personally I think that it would be more sustainable to invest more funding into developing our ability to capture renewable energy sources like wave, tidal and wind power. The seas surrounding us have the potential to supply us with a lot of energy and so I think that we, as a nation, should start to utilise this more. However, I realise that we can’t just switch from using coal-fired power stations and other fossil fuels overnight and so in the meantime it is important to make sure we use a mix of both renewable and non-renewable energy sources. I would be really interested to here other peoples opinions on this issue....... do you think it would  have been better if the government invested money in the Severn barrage instead of the Hinkley Point power plant?

Can the planet cope with the growing population?

This year the global population will reach seven billion people and it is predicted that by 2045 it could reach nine billion. However, can the planet take the cope?

This month I have read two very interesting articles in two different magazines which have both discussed this very issue. I am sure your Geography teachers have mentioned the article in this month’s National Geographic and if you haven’t had the chance to read it yet, I would as it is truly a great article and it manages to link together practically the whole population module (there is a link to the article and a video on the Facebook page).  As I am sure you all know; population theorists are split into two categories – pessimists or optimists. Malthus (pessimist) created his general law on population growth which stated that ‘it necessarily grows faster than the food supply, until war, disease, and famine arrive to reduce the number of people’ in 1798. It is hard to determine whether or not he is right as there has been a population explosion but, even after repeated famines, droughts and wars in Africa for example, historians believe that the world population has not fallen considerably since the Black Death. Instead the  global population has continued to grow most impart due to technological and scientific improvements which have meant that the average life expectancy has risen from 35 years to 77 years. Ehrlich, another pessimist, predicted (in the 1970’s) that “hundreds of millions of people are going to starve to death”. However this too did not occur on the scale Ehrlich predicted due to the green revolution (introduction of high-yield seeds, irrigation and pesticides and fertilizers meant grain production doubled) and although many people are undernourished mass starvation is rare. Ehrlich was right though in terms of his prediction that the global population would explode as, improvements in medicine, saved many people from dying which suggests that population growth is an inevitable side effect of development.

India is a great example of a country which is trying to develop whilst wrestling with the problems associated with a rapidly growing population. Since 1960, India has gained 782 million people and by 2030 its population is expected to exceed China’s. Like Ehrlich, I too, have visited India and can totally support his statement that explained how, in India, there are people everywhere. Clean water, along with food, is one of the main issues in India and this is likely to only get worse as there is growing concerns in India over the country’s water security as all of India’s important rivers originate in Tibet. Tibet is controlled by China who also has issues with water due to falling water tables and the draining of the Yellow River. Threat to India's water security article

 During my time in India I spent 5 days in a school in Chennai that was run as almost a charity and so was free (to a certain extent). From talking to many of the girls at the school I gained the understanding that education totally altered the way they viewed themselves and their futures. Instead of wanting to settle down and have children they now wanted to further their education and have careers first. Children in India, unlike many in more developed countries, don’t take education for granted as they realise that it is the key to the future. They even have a famous saying, which was written in every classroom, in which they ranked teachers just below God. Personally I agree that education is the key to a better future and, from my knowledge of the DTM, I also think that it is key to development. The fertility rate in India is falling, which could be linked to the development of sterilization schemes, but I personally think that it is partly due to the fact that children in India, on average, are a lot better educated than their parents. This has changed attitudes and so, slowly, the idea that the number of children determines social status is being replaced by other ideas. Kerala, which has a literacy rate of 96.6%, is an example of a region in India that supports my belief that education is vital as improvements in education have allowed Kerala to have similar basic human development indices to countries in the developed world.

Space for 7 billion people is not an issue as it is believed that you could fit seven billion people standing shoulder to shoulder in the city of Los Angeles. Even if by 2045 there are 9 billion people on the planet, living on the six habitable continents, demographers believe that the world population density will be just over half of what population density is in France today. Space, therefore, is clearly not an issue but can the world feed 9 billion mouths…….

An article in last week’s New Scientist outlined the findings of the five year modelling exercise performed by INRA and CIRAD (French national agricultural and development research agencies) which suggested that ‘we don’t need to starve in order to preserve the environment’. The results of this model suggested that ‘realistic yield increases could feed everyone, even as farms take measures to protect the environment, such as preserving forests or cutting down on the use of fossil fuels’. To be able to feed 9 billion people the INRA said that waste needs to be prevented as on average, the model calculated that the rich waste up to 800 calories worth of food a day.

New Scientist article - we can feed 9 billion people

 The UK’s Institution of Mechanical Engineers also released a report this week that sided with a more optimistic view of how we can solve the issues created by population growth. The report says that ‘to sustain our future Earth, even as the population hits 9 billion, we already have all the technical fixes we need’. The report claims that the only things preventing this are politics and economics. The report uses the examples of how “market failures” are preventing low carbon energy technologies being used and how, they believe, we produce enough food already to feed 9 billion people but that 2/3 fails to reach mouths, to support their report. In terms of providing water the report says “Forget large dams: increased water storage should come from recharging aquifers with treated waste water and floodwaters”. The report recognises that, as population grows, urbanisation will increase and so slums will become more of an issue but instead of demolishing them the report says that they need help to improve as otherwise they will just return.

New Scientist article - Housing 9 billion

Personally I am undecided on whether or I would class myself as a population pessimist or optimist as I agree with parts of both Malthus’ and Boserup’s argument as GM crops and renewable energy sources are examples of how we are developing solutions to problems caused by population growth but, on the other hand, what would the size of global population be if countries had not experienced loss through famines, droughts, wars and natural disasters?

On a totally different note, I think the A2 students are about to start a climate module and in the same edition of the New Scientist there was an interesting article on climate predictions and how they are formed. It also explains why predictions differ so much and change frequently. I was surprised to discover how much bearing clouds have on whether or not countries will face warming or cooling as some clouds (high, thin ones) tend to stop more outgoing radiations (low thins ones would have the opposite effect and cool the climate). Also that both the size of a clouds water droplets and the holes within the cloud greatly affect a clouds ability to reflect incoming radiation. Even if you are not studying climate I think it is an interesting read for anyone doing Geography (to view the article online go to this link http://www.newscientist.com/search?doSearch=true&query=casting+a+critical+eye+on+climate+models , click on the first article and then you have to register to see it but it’s free to do so).

I am really sorry about the length but I didn’t realise quite how much I had written until I had finished it.  I promise I will try and make them shorter in the future…..

First Blog -Ageing populations and the possibility of a stage 6 on the DTM

This is my very first blog and I am not 100% what to write about or how to write it and so I am going to apologise before I start as this is likely to be all over the place and not very good.

Firstly I would like to congratulate all of my fellow students for completing the skills exam - I am sure you have all done really well. Most of you also got what you wished for in terms of it being a human paper rather than a physical one. I hope you all have a relaxing weekend ahead of next week when we get to start the new module - ENERGY!

I realise that you are all probably fed up with thinking about population due to having to revise it intensely over the last couple of weeks but I am going to talk a bit about population today as I had a very interesting discussion regarding population change with the Geography department this afternoon. Ageing populations are a problem facing many of the most developed countries in the world. China is one of them and currently has 167 million people over the age of 60 and a million people over 80. This causes huge problems in countries as it depletes the workforce and increases the number of dependants. The One Child Policy has made this issue worse in China as there are only two adults to look after four elderly relatives at best. This means that the Chinese tradition of adults looking after their elderly relatives is becoming more and more unfeasible and so many elderly people end up dying alone. This has provoked the Chinese government to consider making it a legal requirement for adults to look after their elderly relatives (this is the link to the article if anyone is interested http://www.bbc.co.uk/news/world-asia-pacific-12130140 ). The article presents a very interesting way of dealing with one of the problems associated with an ageing population and, like my Geography teacher; I too wonder how a proposal like this one would be received in this country. The comments are also worth a read and I think it is very interesting to see that quite a lot of people, including some from China, would actually support this proposal as they recognises that, with around 167 million people aged over 60, that care for the elderly is a huge problem in China. However this proposal isn’t going to solve the issue of an ageing population and surely the problem in China is going to escalate. Anyway this then prompted me to ask the question, do you think that there are any realistic ways of preventing populations from ageing or do you think that it is an inevitable side effect of a country developing to stage 4/5 of the Demographic Transition Model, to some of the Geography teachers. They all agreed that ageing populations are an inevitable side effect of development and that there is very little that can be done to prevent this. The CBR of a country would have to be raised to do this but this would be very hard to do mainly due to the emancipation of women, improvements in contraception and their availability and vast improvements in medicine which has led to a longer life expectancy and a lower IMR. One of the Geography teachers felt that women alone and their desire to have equal rights in terms of careers and education was the sole cause of ageing populations but I must admit that I do not entirely agree with their point of view! France is a perfect example of a country who tried to introduce a pro natal policy to increase its CBR but even the incentives offered have done little to persuade most women to have more children. This article outlines some of the incentives offered in France and in other European countries...... http://www.guardian.co.uk/world/2005/sep/22/france.jonhenley1 

The main factor that has caused the UK's population to age is the baby boomers who have now reached retirement age. As more and more of these baby boomers reach retirement age it is possible that the UK's CBR will fall below its CDR which will cause us to move into stage 5 of the DTM but the question is what happens after that? There isn’t a very pleasant way of saying this but when all of the baby boomers die what will happen to the UK's population structure? Is there going to be the need to add an extra stage on to the DTM and if so what will stage 6 look like?

If you have any ideas regarding a possible stage 6 then please comment as I myself am a bit stuck for ideas on what could happen. Sometime over the weekend I will try and write a blog about population growth, in response to this month’s excellent article in the National Geographic, to wrap up the population unit - that is if I remember to!