The Science of Climate Change. Dr Caroline Cox Space and Atmospheric Physics Department Imperial College, London

Transcription

1 The Science of Climate Change Dr Caroline Cox Space and Atmospheric Physics Department Imperial College, London

2 Climate Change is a very popular topic...

3 But also not very popular... Global warming? More like Global Lying! Nothing we do can affect the Climate! Armchair Scientists!

4 Scientists say Most of the increase in global average temperatures since the mid-20 th century is very likely due to human influence.

5 Why don t people like the theory of Climate Change? 1. Climate change is bad news It s our fault 3. It is not understood

6 What is Climate? 2-6 C C Winter Summer London

7 Mediterranean 6-13 C Winter C Summer Athens

8 Northern Europe C C Winter Summer Moscow

9 Climate Climate can be described in terms of both the average Temperature And Weather over a long period of time

10 Temperate climate overall...but it hasn t always been like this A brief history of Earths temperature

11 The climate has always been changing

12 Rapid Climate Change The Earth has been HOTTER than it is now, and COLDER than it is now, so if it changes again, what is the problem? How quickly a change happens also matters!

13 Why has the Earth s temperature been changing? Look at what keeps the Earth warm

14 SPACE EARTH

15 SPACE No atmosphere Heat going up Solar energy -18C EARTH

16 SPACE With atmosphere Heat going up Gas molecules Heat coming down 15C EARTH

17 Greenhouse Effect We get a greenhouse effect because the Sun and Earth emit different types of radiation

18 Radiation in everyday life Radio Microwaves Visible ultraviolet X-rays Infrared Gamma -rays

19 Radiation from the Sun and Earth Infrared radiation cannot pass through the atmosphere easily Solar radiation can mostly pass through the atmosphere

20 The Earth emits infrared radiation Visible plus infrared visible

21 Sun and atmosphere Can changes in these cause the climate to change?

22 Solar influence to Climate 6000C The Sun provides all the Earths power. It s VERY important!

23 Solar influence to Climate But the amount of power we receive from the Sun changes due to... The Sun just not emitting as much power all the time Or the Earth moves sometimes closer, sometimes further away from the Sun during its orbit over many, many thousands of years Some scientists think the ice ages were caused partly by the Earth moving further from the Sun.

24 Volcanoes can affect the climate And we can also see effects on the Earths temperature when the Sun is dimmed slightly by volcanic eruptions.

25 The Sun The Sun influences the temperature on Earth, as do volcanoes. NATURAL EFFECTS We don t have any control over these, however, we have some effect on what goes into the atmosphere.

26 The Atmosphere

27 Top 4 gases that make up a dry atmosphere? oxygen Carbon dioxide nitrogen argon Why the concern about CO 2?

28 SPACE Heat going up Greenhouse Gases i.e. CO 2, Methane Heat coming down 15C EARTH

29 Carbon dioxide levels are going up! Concentration of CO2 has never been higher and has never increased at the same rate as we see today There is another very important greenhouse gas in the atmosphere I haven t mentioned yet...

30 Water vapour everywhere! The most important Greenhouse Gas

31 The water vapour feedback loop

32 Feedback loop

33 More feedbacks..clouds What do you need to make a low cloud? Water vapour Heat Tiny particles

34 Making a cloud Low pressure, cold High Pressure, warm

35 The low-cloud feedback Cooler

36 Low-cloud feedback loop

37 So what are we doing about Climate Change? There are lots of different ways the climate might respond to rising CO 2 levels Scientists are trying to work all of these out, so we can predict what changes will occur.if we know, then we will cope with Climate Change much better!

38 We have solved big problems before! When we found a hole in the ozone layer, everyone stopped using the chemicals that were causing it to get bigger. So now, if everyone does their bit to reduce CO 2 emissions by saving energy, we can still reduce the effect of Climate change!

39 My Research I study Cirrus Clouds..

40 My Research. How much do cirrus clouds warm the atmosphere?

41 Experiment Cirrus cloud

42 The instrument TAFTS

43 Research aircraft

44 Inside

45 The hangar and runway at Cranfield

46 Typical flight day Get out of bed 6.00am Evacuate instrument and fill detectors will liquid helium and nitrogen to cool Flight briefing meeting 8.00am Instrument on aircraft 8.30am Security checked 9.00am On aircraft 9.30am Take Off 10.30am

47 Fly over to location Low level flying over sea! (50 foot/ 15m) Fly to top of cirrus and profile down Other manoeuvres (orbits, dips) Land 4.00pm Flight de-brief 4.30 Instrument Off, go back to hotel

48 TAFTS has travelled all over the world

49 Being in research means You get to travel.. You can work on almost any kind of topic you want. Washington DC Vienna, Austria You can work on problems that will help improve peoples lives. Grenoble, France

50 To conclude I hope you understand Climate Change better now I hope I have showed why it is important to study this topic. Thank you for listening!

51 Figure references Slide 1: slide 2: from websites of BBC, Daily Mirror, Telegraph, The Independent and The Sun slide 5: and Looby Dreamstime.com slide 6-8: bbc weather website slide 10: slide 11: and And ambrosewilson.com slide 13: slide 18: argos.com and Sun Children 160 x k - jpg and slide 19 slide 20 slide 21 Slide 27 and and and knowledge.allianz.com and Slide 29 Slide 30 Slide 33 Slide 37 Slide 38 Slide 39 Slide 41 Slide 42 and 43 and 46 Slide 44 google earth Slide 47 Slide