Last week I started an online Future Learn course which anyone can take part in. For those who haven't heard of this, people who sign up to the course are advised to spend a certain amount of time each week studying the chosen subject and the learners are provided with different kinds of learning materials e.g. a video lecture of about 4 minutes or an article to read. Discussions on each sub-topic are encouraged and at the end of each week a small test is taken and then all members of the course are invited to reflect upon what has been learnt and also other things such as themes of the week, difficult aspects of the topic, interesting information any further research.
For those not taking the course and who haven't heard of this type of online learning, the following link will give you a taster of the kinds of courses you can embark upon.. https://www.futurelearn.com/courses/categories
Climate Change: Challenges and Solutions - Week 1
1. Key Scientific Principles that explain Climate Change
- An example: the greenhouse effect - greenhouse gases such as water vapour, carbon dioxide, methane and nitrous oxide act like a 'blanket' around the Earth and prevent heat from escaping from the atmosphere into space.
- An interesting fact: Without the 'greenhouse effect' the planet would be about 30 degrees Celsius colder and would make the Earth uninhabitable to most lifeforms.
- The human effect: human activities such as burning fossil fuels is changing the concentrations of the greenhouse gases and this along with many other human led processes will have consequences.... Earth will become warmer, weather conditions will change dramatically, sea ice will melt indefinitely, sea levels will rise and crop growing will shift to accommodate for changes in atmospheric gases.
- A great diagram explaining the simpler aspect of the greenhouse effect:
|climate.nasa.gov/causes/ [accessed 19/01/2015]|
2. Climate System Feedback Mechanisms
- Water Vapour - this feedback loop operates within the climate system and forms part of the water cycle. The water cycle brings together all the key components of our climate system. The flow diagram below is my understanding of the water vapour positive feedback loop depicted in the simplest way possible.
- Ice albedo - albedo was a new term for me entering into this course.
Ice and snow have a high albedo and therefore reflect heat radiation back towards space. The ocean has a low albedo and absorbs heat radiation.
- Radiation - I couldn't find a really simple flow diagram of this NEGATIVE feedback loop so I hope this explains it correctly....
The three illustrated feedback loops act within a system, alongside many others, to regulate the climate to a particular state.
Other things to contemplate....
Important themes - the difference between climate and weather "The difference between weather and climate is a measure of time. Weather is what conditions of the atmosphere are over a short period of time, and climate is how the atmosphere "behaves" over relatively long periods of time." - (http://www.nasa.gov/mission_pages/noaa-n/climate/climate_weather.html#.VLz4oCusX0c
Difficult aspects - in the video explaining feedback loops, the radiation feedback mentioned the Stefan-Boltzmann effect and this law is quite confusing and difficult to understand for my non-physics minded brain!! I think this website http://www.global-climate-change.org.uk/1-2-3.php is probably quite good at explaining it but it is over my head completely!
Most interesting aspect of week 1? - This is my first Future Learn course. The first week was very interesting as a whole - otherwise I wouldn't have been motivated to continue learning or to write this blog post!
Further research - The term albedo prompted me to read outside the course material as did Stefan-Boltzmann. In the last article the term 'troposphere' was mentioned and this led me to research all the different layers of the Earth's atmosphere.
I hope my regular readers haven't minded this 'unusual' post (you may have a few more to put up with!) but I do hope to finish off my post on my visit to Southern Spain which will include a few more photographs :)
I also hope that anyone who may read this from the Future Learn course has enjoyed the post and will feel welcome to comment below :)