Week 7 - Adaptation & Mitigation

The poorest week by far.

A video supposedly about adaptation and mitigation focuses on a new build school that's been built to be zero carbon, stay cool in summer, and generate it's own power.

All very nice but how does it mitigate climate change? Yes, if it were applied to all new builds, it might just scratch the surface of the problem, but we all know that's not going to happen any time soon. Every building would cost a fortune for a start.

What would have been better would be to show an old school being retrofitted with cost efficient carbon cutting and adaptation measures. That would have been far more interesting, realistic, and on topic.

And then, to compound things, we were asked to 'browse' a 75 page document on mitigation and adaptation in, would you believe, new build houses.

ARGHHHHHH!! The UK alone has 25 million existing homes, very few of which are even close to zero carbon. They're the problem! How do we get them sorted out?

Then we get the classic "Decarbonising energy is all very well but what about..." argument in the form a video about NIMBYs. Yes, I've heard it all before, so where are the SOLUTIONS?

If we are to have any chance of keeping climate change below 2 degrees C, global carbon emissions have to level off (and fall quickly thereafter) by 2020. We need effective, cost efficient solutions now and that may mean we have to make some tough choices.

If we want things to stay the same, things are going to have to change.

Week 6 - Effects of climate change on Humans

This week we covered the topics of urban heat island and food security.

Urban heat islands
Here we looked at the way cities tend to be several degrees warmer than the surrounding countryside making heatwaves all the more dangerous. Heat islands are caused by large and/or densely packed buildings absorbing and re-radiating heat, whilst there's little to cool things off (like open spaces, woodland, circulating air, and evaporating water).

70,000 people died in Europe's 2003 heatwave. Most deaths occured at night near the top of tall buildings. At night, because people would normally get the chance to cool down then but can't during a heatwave. At the top of tall buildings because they store more heat and heat rises...

Given that the world's population is tending to migrate towards cities (I believe some 50% or more will be living in cities by mid-century) this problem can only get worse in a warming world unless some way of reducing the effect is found.

Food security
Pests and diseases are on the increase thanks to climate change. We depend on 3 main crops, if these pathogens sweep through any one of these (in a similar way to Ash Die-back, Dutch Elm Disease, and Acute Oak Decline) and there'd be mass-starvation, food riots and, in the developed countries food inflation.

This too is set to be more of a threat as the world population increases to around 9.2 billion by mid-century: We may need to double crop yields by then to keep up with the demands of the increasing population, especially the growing middle classes.

Climate change, rising sea levels, mass extinctions, urban heat islands, ocean acidification, over population, water scarcity, and mass starvation. That's what our kids have got to look forward to.

Week 5 - The impacts of climate change

This week we covered the effects on the cryosphere and ocean acidification.

The Cryosphere
i.e those areas of the Earth covered in ice or show such as ice sheets, glaciers, permafrost, and snow fields.

Most of the world's ice is contained in the Antarctic and Greenland icesheets. These are so big that, were they to melt completely, sea levels would rise by 65 metres. If you want to get an idea of what that would mean to your part of the world try here.

Unfortunately, the Greenland sheet is losing mass at an accelerating rate and parts of western Antarctica are showing signs of vulnerability too. We learnt about some of the things that influence this including how melt water can accelerate the rate of flow of glaciers and buttressing (which can slow mass loss down).

Ocean Acidification
The oceans act as a CO2 sink, absorbing around half of our carbon emissions. Unfortunately, this is leading to the oceans becoming more acidic. The pH has decreased by 30% since pre-industrial times. This could seriously compromise the ability of marine organisms to build and retain shells and skeletons. They may even have problems getting rid of CO2 from their bodies leading to acidosis.

These problems may result in the extinction of many shell forming organisms. If any of these are near the bottom of food chains it may lead to the collapse of the whole food chain. Mass extinction anyone?

Why should we care? Because the sea provides us with a significant part of our diet. For many of us, fish and shellfish is a nice-to-have not an essential, but for some populations, it is a staple part of their diet.

Week 4 - Climate Models and Geoengineering

Two controversial areas this week.

Climate models are computerised simulations of the Earth's climate which can be used to predict future climate based on a given set of variables.

The principle is fine and can be tested and tuned against past climates. It's important to realise that they don't predict precisely what will happen but give a general idea of where things are likely to head.

For this reason they are considered controversial by climate sceptics/deniers. The rest of us see the models for what they are: A useful tool.

By contrast, Geoengineering is controversial for good reason: It's playing god.

You see, if you accept that computers can never truly model all the complexity of the climate down to the finest detail, how can you expect to use something like stratospheric aerosols on anything other than a wing and a prayer? It's nuts.

But there are lot of vested interests out there who want and need a silver-bullet, so don't be surprised if geoengineering gets deployed anyway.

That's when we'll KNOW we're screwed.