Climate Change Week 7

It's the penultimate week of the Climate Change MOOC and another interesting experience.  This week we covered the mitigation of carbon emissions, adapting the built environment to climate change and the human resistance to renewables, i.e. NIMBY - Not In My Back Yard!

I learnt that the world's primary energy consumption is 470 exajoules, that's 470,000,000,000,000,000,000 joules - wow!  That's a big number but in terms of a 'currency' that we might understand, it equates to each person in the world using 2kw of power all day, every day.  I know that's a lot but somehow it doesn't sound as much as 470 exajoules.  Whatever, one route towards reducing carbon emissions is for each of us to reduce our current consumption of electricity, much of which is produced by burning fossil fuels.  The other route is to make more use of renewable energy.  Now I don't think either of these two routes should be news to anyone.  But like all simple statements of WHAT has to be done, there are rarely equally simple statements of HOW it should be achieved.  Why?  Because, in my opinion, the HOW is down to each of us individually and there is unfortunately a view held by many that the solutions to climate change are someone else's problem.

Attitudes need to change and we were introduced to Montgomery Primary School in Exeter, which is the first Zero Carbon Passivhaus school in England.  Now not only do I think it's a good idea for new buildings to be Zero Carbon, but building a primary school that way means that young children are introduced to how WE ALL need to respect and sustain our environment.  The school claims to have an electricity bill of £0 per year and the excess electricity from its solar generators provides a small income to maintain the equipment - wonderful!

We also learnt how construction methods in the UK's urban environment need to adapt to the expectation of warmer, drier summers and much wetter winters.  This could involve adopting some of the practices currently employed in Mediterranean countries.  We were introduced to a wealth of information on this subject and I suppose new building practices can be introduced 'forcibly' by regulation.  There will, however, be an inevitable impact on cost.

The final part of this week's course was about NIMBYism - Not In My Back Yard!  If we're honest, there's a bit of NIMBY in all of us.  We love the idea of renewable energy so long as it doesn't affect our personal space.  In other words, we're selfish!  Now there are all sorts of ways that governments can try to counter NIMBYism, including siting wind turbines, for example, away from the 'back yards' to offshore environments.  Another way is better communication on the need for renewable sources.  If all else fails, providing community benefits packages to the affected areas can be an incentive to accept renewable energy installations.  But social research has shown that even these methods do not effectively address people's innate resistance to change.  My view is that the seriousness of climate change has not really been taken onboard.  We have to recognise the 'back yard' is now the planet, not our own cozy little communities.  National boundaries are, after all, man-made inventions that only man respects.  Weather systems have no boundaries and therefore carbon reduction strategies have to be global.  That doesn't mean that the environment where we live should not be important to us.  Of course it should.  But NIMBYism per se mustn't be allowed to get in the way of the development of our global society.

That's my thought for the day and I look forward to Week 8!

Climate Change Week 6

This week the course focussed on the impacts of climate change on human systems and in particular, the built environment and food security.  In recent years, I have developed a strong interest in systems thinking, which in simple terms means understanding by putting together, rather than understanding by taking apart.  Systems thinking requires a comprehension of not just the component parts of the system but also the interdependencies.  Well as I proceed through this course, it is quite obvious to me that climate change cannot be separated from everything else that affects our planet. The subject matter for this week reinforced that view.  When trying to appreciate the complexities of the planet, there are no simple system models and therefore it is necessary to break it down into subsystems that are easier to understand.  That said, we cannot ignore the subsystem interdependencies.  This week we started to explore the interdependencies between the climate and human existence.

Urban heat islands are interesting and probably something that we are all aware of.  I live in a rural environment in Turkey and about 2 km from a small town.  I notice when I drive from my home into town, the display on my dashboard of air temperature can increase by as much as 2 deg C on the journey.  So that is a very good local example of an urban heat island.  We learnt about the factors that create the temperature differential and how the majority of deaths during heat waves occur in high buildings at night.  The deaths are usually from dehydration and hyperthermia.  Now one thing I notice when I travel between the UK and Turkey in the summer months, is that 25 deg C in an English town can feel far more uncomfortable than, say, 35 deg C in a Turkish town and my view is that the difference in comfort can at least in part be explained by the contrasting construction methods in the two countries.  In the Mediterranean region of Turkey where I live most of the buildings are white or light-coloured and many of the urban roads are paved in light-coloured material, rather than having a black tarmac surface.  So maybe if the Northern European region is going to experience more frequent heat waves, their city and town planners should look to Southern Europe and Asia Minor for best building practices!

The course material on food security was extremely thought-provoking, because it highlighted the strong interdependency with climate change, which before embarking on this course, I hadn't considered.  Since the 1960s the world's agricultural industry has been subjected to what is known as the Green Revolution.  There has been a huge improvement in efficiency by the increasing use of fertilisers, herbicides, pesticides and fungicides, as well as more mechanisation and vast areas of land devoted to monocultures, i.e. single crop varieties.  The efficiencies might be improved but the impacts of potential crop failure are far more serious.  When a vast area is hosting a single crop, then in the event of pests or pathogens attacking the crop, there can be a dire food shortage.  A classic historical example is the Irish potato famine in the 1840s, which led to a million people dead from starvation and a similar number emigrating to the New World.  Climate change is causing the movement of pathogens to new geographical areas, threatening species of crops that were previously unchallenged.  Needless to say, scientists are on the case, looking at ways to increase the resistance of crops to disease.  What strikes me about this problem, however, is that it is exacerbated by two social factors.  Firstly, a rapidly increasing population and therefore a corresponding increase in the demand for food.  Secondly, a situation in the world today, where obesity sits alongside starvation - Gandhi said: "There is enough for everyone's need [in the world], but not enough for everyone's greed."  Both these problems have solutions.  Population increase can be brought back to a sensible level by birth control and obesity could be significantly reduced by sensible diets.  But how do these simple solutions become realities?  Well I suppose it's by education.  Now this subject could become another blog post in its own right and I could be accused of straying from the subject of climate change.  But it brings me back to my opening remarks on systems thinking.  The issues that are being raised by climate change, including this week's focus on human systems, show how interconnected nature is.

It's been another great week on the Climate Change MOOC and I will conclude this post with a quote from John Muir: "When one tugs at a single thing in nature, he finds it attached to the rest of the world."

Climate Change Week 5

This week we looked at the impacts of climate change on the cryosphere (the portions of the Earth's surface where water is in solid form) and the oceans.  Once again we were bombarded with a lot of information, some of which will regrettably fade from my memory with time but hopefully some salient facts will be retained.

The first fact, relating to the cryosphere, that will certainly stick in my mind, is the amount of ice locked up in the Antartica and Greenland ice sheets.  If these sheets were to melt completely, which hopefully is highly unlikely, the sea water would rise by 65 metres!  That is phenomal and one fact that I will certainly not forget!  I did some Internet research and here's what the UK and Northern Europe would look like if the sea level increased 65m.

Frightening isn't it?!  Although this disaster scenario is unlikely, the ice caps are reducing and Greenland has been significantly affected over the past two decades.  In particular, there was an above-normal ice melt in 2012.  The situation in Antartica is no better.  In particular, the West Antartica Ice Sheet, which is grounded below sea level, maybe prone to collapse.  It's a low-probability, high-magnitude event and the most recent numerical model predicts a sea level rise of 3.3m if this event was to occur.  This week's course material also included photographic evidence of massive shrinking of the glaciers on the Himalayas over the past 100 years.  The retreating glaciers could eventually have an impact on the supply of water to billions of people in the region.

Well after that depressing tale, what about the oceans?  We learnt about ocean acidification.  Here's another fact I will remember.  The oceans cover 70% of the planet (yes, well I knew that before the course!) but because they are so deep, they contain 99% of the living space for animals on the planet (now that was news to me).  Climate change is having an impact on marine invertebrates, which account for 76% of the species in the oceans.  The oceans absorb a third of the atmospheric carbon dioxide and that's always been the case.  The problem with the rapidly increasing carbon dioxide levels is that the natural buffering within the oceans, known as the carbonate buffer, which soaks up hydrogen ions, is losing its effectiveness and the sea is becoming more acidic.  Here's some more frightening numbers, the oceans had been stable in terms of alkalinity for millions of years, but since the Industrial Revolution, the hydrogen ions have increased by 30% and if we continue to release carbon dioxide at the current rate, there could be a further 120% increase by the end of the century.  Can marine animals cope with such rapid changes?  Probably not.  Indeed, the shells of some invertebrates are already showing signs of dissolution.  The ramifications of these changes are still under research but there will be inevitable effects on eco systems and the food chain.

So it's been an interesting week and in some respects quite depressing because the changes to the land and oceans are clearly not reversible.  But the rate of change is to some extent, under our control.  The complexity of the system is awesome and as I gain a better understanding of the constituent parts, the more I want to learn.  So roll on week 6!

Climate Change Week 4

I have now completed 50% of the Climate Change MOOC.  Just like a good holiday, time is going too quickly.  It's really enjoyable.  This week we learnt about two topics that are of particular interest to me - climate modelling and geoengineering.  I think it's important to understand some of the science behind predicting climate change including how the models are constructed and verified.  Likewise, whereas the obvious solution to the planet's problems would appear to be a drastic reduction in CO2 emissions, another option, which is somewhat controversial, is geoengineering.

The Met Office in the UK has very advanced computer models that are used for weather prediction and many of the processes that are employed to forecast the weather over a five-day period are similar to those required to predict the climate over 250 years.  The computational demands are huge and even with the Met Office's latest super-computer, a typical climate simulation can take three months of elapsed time.  But a model is a model and despite all the fancy charts and spreadsheets, in order to have credibility any model should be validated.  The easiest way to do this is to run the model with past data and see if the computed result matches what actually happened.  The results with data collected over the past 150 years, since reliable records were kept, are interesting.  We know the globe has warmed by about 0.8 degrees C in that timeframe.  When only the natural factors were input to the model, which include variations in the sun's output and volcanic activity, the climate simulation followed recorded data up to about 1970.  After that date the simulation showed the global temperatures cooling, whereas in reality there was significant warming.  However, when human factors were added to the inputs to the model, particularly the increase in carbon dioxide due to the burning of fossil fuels and deforestation, the simulation followed the observed climate very closely.  So it would appear we have a good model.  This should give confidence in predicting climate over, say, the next 250 years BUT only if we can predict human behaviour, and that's a big BUT.  The way the scientists cope with the vagueries of the human race is by assessing a number of different scenarios.  These scenarios include variables such as population growth and the ability of mankind to take the appropriate actions to reduce carbon dioxide emissions.

What about geoengineering?  Well, I have stated previously that I have tried to be open-minded on this course in order to assess objectively the expert opinions.  I have to admit that it didn't take long for me to have grave concerns about geoengineering, which is the use of technology to control the climate.  There are two branches of geoengineering, carbon dioxide removal mechanisms and solar radiation management.  The latter, which includes spraying aerosol particles into the upper atmosphere, really scares me.  Apart from the obvious unknowns and therefore high probability of unintended consequences, I have a real concern that if these techniques were pursued with vigour, the world's politicians would see it as a good reason to avoid any short-term painful decisions associated with meeting tough carbon dioxide emission targets, and would continue with business-as-usual government policies.  What a disaster!

It's been another thought-provoking and interesting week.  I am getting more concerned about the future and particularly the demands that are being placed upon the planet's resources by a rapidly increasing human population.  Maybe extreme climatic conditions will lead to self regulation of the population - is there a model for that?!  Whatever, the course is billed to cover challenges and solutions.  I think the challenges are already very clear, but whilst the low risk technical solutions are common sense, as is often the case, common sense is not very common!  I look forward to week 5.

Climate Change Week 3

It is now time to reflect on week 3 of the Climate Change MOOC.  This week has been about the here and now.  Or at least the past 150 years rather than the events of millions and billions of years ago discussed in previous weeks.  There is no doubt that the technology that is now available and the amount of effort put into examining climatic trends, does give confidence in the expert assessments of climate change.  It is also an indisputable fact that there has been a significant rise in the Earth's temperature during the 20th century and up to the present time.  The most recent decade is the warmest on record since measurements have been taken over the past 170 years.  This has resulted in rising sea levels from thermal expansion and the melting of land ice.  It is worth noting that, contrary to some peoples' views, melting sea ice does not increase the level of the oceans because floating ice displaces the same volume of water as it would if it were liquid - Archimedes principle.  There have also been some extreme weather events - floods, heat-waves, hurricanes, etc - but apparently it's not possible to attribute a particular event to climate change because it might be due to natural fluctuations.  Interestingly, although the world is getting warmer and the Arctic ice cap is reducing in size, the Antarctic sea ice is expanding.  This paradox is explained by the influence of winds and waters in the southern oceans.

As we know, carbon dioxide is one of the key gases in the warming blanket around the planet and this week we learnt more about the carbon cycle.  10 petagrams of carbon (a petagram is 10 to the power 16 grams!) are released into the atmosphere each year as a result of human activities.  90% comes from the burning of fossil fuels and the remaining 10% from deforestation.  Out of the 10 petagrams of CO2 released each year, the atmosphere increase is about 4.5 petagrams.  The rest is absorbed by the land and the ocean.  Without this absorption, the atmospheric CO2 would be much greater and we don't really know how these carbon sinks will be affected by climate change.  I did an analysis of the emissions in metric tons per capita for the following countries:

Turkey (where I live) 4.1

UK (where I come from) 7.9

USA 17.6

China 6.2

India 1.7

The emissions from China are increasing year on year, which is hardly surprising.  China is fast becoming the manufacturing centre for the world and as an increasing global population demands more manufactured goods, China's CO2 emissions will increase.  This assumes, of course, that the increase in manufacturing capability still depends on the use of fossil fuels.

After three weeks into the course, I am now convinced that anthropogenic (I love that word even though 'human-induced' is probably more widely understood!) activities, are strongly linked to the rise in global temperatures.  What, in my view, is debatable is whether recent extreme events are natural fluctuations or exacerbated by human activity.  I have found the discussions interesting.  I do feel that some participants have very fixed views on the cause and consequences of climate change, maybe I do!  But I really am trying to keep an open mind and evaluate the material objectively in order to improve my knowledge of an issue that is so important to the future of humanity.

So onwards and upwards, roll on week 4!

Climate Change Week 2

So it's week 2 of the Climate Change MOOC (Massive Open Online Course) and it's continuing to live up to my expectations.  Before I get into my reflections for this week, it is worth making a few comments on the MOOC process, which is new to me.  I had concerns that because MOOC is MASSIVE, with unlimited participation and open access via the web, it would be unmanageable.  But my concerns were certainly unfounded.  In fact, far from being unmanageable, it actually seems to manage itself, rather like Facebook, LinkedIn, Twitter, et al.  So although there are obviously many participants with different backgrounds, skill levels, aspirations, etc., the way in which each participant 'tailors' the course to suit his or her requirements, results in an individual learning experience.  So well done FutureLearn, I'm impressed!

This week we have been studying past climate change starting at around 4.5 billion years ago.  The Earth has been habitable for all that period but has seen a tremendous range of climatic conditions.  Interestingly, 4.5 billion years ago the sun was about 25% to 30% less bright than now and yet if today's sun was 'turned down' to that level, the planet would freeze.  But it didn't.  The reason it was warmer than expected, was because of a thicker layer of warming gases.  OK but as the sun warmed up over the years, why didn't the planet get much hotter?  The continents weathered as a result of rain water and carbon dioxide forming a weak acid, which dissolved rocks and the carbon washed into the oceans where it was used by organisms to form shells.  These ultimately were deposited on the ocean floor to form carbonate rocks.  This is how the carbon was taken out of the atmosphere and the climate self regulated.  Clever isn't it?!

There were two notable periods in the planet's history, 2.2 billion and 700 million years ago, when the planet froze and became a giant snowball.  The theory is that on both occasions something happened to cool the planet so the ice caps expanded.  As they grew they reflected more sunlight, causing more cooling and more ice cap growth until the whole world was covered in ice.  The freeze was broken by volcanic activity, which is not affected by the big freeze, this pumped carbon dioxide into the atmosphere, thus creating atmospheric warming, and so on.

We learnt about more recent climate change in the past 2 million years.  Some of the changes in the past thousands of years have been totally predictable and are as a result of variations in the shape of the Earth's orbit and the angle and location of its axis.  The three factors affecting the sun and therefore the Earth's climate, are eccentricity (change from circular to elliptical orbit), obliquity (change of tilt of the Earth's axis and precession (wobble of the Earth's axis).  Evidence of climate change was explained and particularly before modern times when measurements were (and are) taken under carefully controlled conditions.  Methods that are employed include tree rings and ice cores.

Finally we discussed the relevance of the fact that on 9 May 2013, carbon dioxide levels in the atmosphere reached 400 parts per million.  This level has not been reached since the Pliocene period, three to five million years ago.  The temperature then was about 2-3 degrees C higher than now.  Are there any conclusions that can be drawn from that?  Well many participants think there are, but my own view is that it is too simplistic to relate the Earth's temperature solely to the increase of man-made CO2.  That said, I am still a strong advocate of the need to reduce significantly man-made CO2 emissions.

I was less hasty this week before doing the course test and it paid off with a better result!  I am looking forward to week 3.

Climate Change Week 1

I have started an online course from FutureLearn - https://www.futurelearn.com.  The course is 'Climate change: challenges and solutions', led by the University of Exeter in the UK.  It is my first experience of an online course and I am thoroughly enjoying it.  The course lasts eight weeks and at the end of each week the students are required to reflect on what they have learned.  So for the next eight weeks, my blog posts will record my reflections.

The greenhouse effect is fundamental to understanding climate change but the greenhouse metaphor isn't a good one.  The heat in a greenhouse escapes through the glass but a small amount gets trapped.  The greenhouse actually warms up because of prevention of airflow, which stops the loss of heat by convection.  This is a similar effect to the heat in an unventilated car on a hot day, which is why it is a dangerous place to leave your pets.  This contrasts with the earth that is kept warm by a 'blanket' of gases.  The most significant gas is water vapour, but the others are carbon dioxide, methane, ozone and nitrous oxide.  The earth reflects about 30% of the sunlight that it receives, which means it has an albedo of 0.3.  Ice and snow have high albedos, i.e. reflect a lot of the radiation, whereas the oceans have low albedo, i.e. absorb a lot of the radiation.  If there was no reflection, the earth's average temperature would be around -18 deg C, but the blanket of gases warms the earth's surface to an average of around +15 deg C.

Climate can be thought of as a highly complex system with feedback mechanisms that produce self-regulation.  The key system components are the atmosphere, the hydrosphere (oceans, rivers, lakes), the biosphere (living things), the cryosphere (ice and glaciers) and the lithosphere (surface of the earth's crust).  Heat from the sun causes water to evaporate from the hydrosphere and biosphere.  Clouds are formed, which precipitate (rain and snow) and water returns to the earth's surface.  Water then returns to the hydrosphere, or if it is frozen snow it can enter the cryosphere.  Sunlight on the cryosphere can transform it into vapour by a process called sublimation.  The water cycle can be affected by many factors involving human activity.

There are many feedbacks in the climate system - closed loops of cause and effect.  Some feedback loops have the mathematical terminology of positive, because they are reinforcing.  Some feedback loops are termed negative because they are balancing.  Here are three examples of feedback in action within the climate system:

The first example is when water evaporates in the atmosphere, the molecules of water vapour absorb radiation from the earth and vibrate.  They then re-emit heat radiation, resulting in further warming.  This is positive, reinforcing feedback.

Another example of positive feedback is when solar radiation hits sea ice, most is reflected because of the ice's high albedo.  The ocean's surface, on the other hand, has low albedo and absorbs most of the radiation.  So as the system warms up, the sea ice melts, which increases absorption by the oceans, warming the sea water, causing more ice to melt, and so on.

The final example is negative feedback.  All bodies give off radiation and the warmer the body the more radiation it gives off.  When it gives off more radiation, that cools it down.  This is known as the Stefan Boltzmann effect or the Planck feedback.

So this complex climate system has a multiplicity of positive and negative feedback loops that self-regulate.

That's my summary of the first week's theoretical aspects from the course.  But one other aspect that really registered with me was appreciating the difference between weather and climate.  Weather is really the day-to-day elements that we experience such as temperature, rain and wind.  Climate change on the other hand, looks at long-term (30 years+) changes in weather.  Where I live in Turkey, the climate is temperate Mediterranean, the characteristics being long hot and dry summers, cooler and wetter winters.  We have all been around long enough to experience all sorts of weather conditions but even in my advancing years, I don't think I could seriously make objective judgements on climate change like, for example, increases in average temperatures in some parts of the world.  So weather is all about short-term conditions that are easy to measure and evaluate.  Whereas climate variations are all about long-term changes, which are assessed by averaging and probabilities.  This really wasn't obvious to me until I started the course.

So it's been very informative and good fun so far.  My only mistake was that I rushed into the test for the week, which was foolish because I dropped a few points.  Next week I won't be so hasty!