The Return of the Clouds

1
The Return of the Clouds

• Are Clouds Self-Organised Critical Systems?
• Gillian Cupitt

2
The Return of the Clouds

• What is Self-Organised Criticality?
• Examining Fractals in clouds
• Looking for periodicity

3
What is Self-Organised Criticality?

• Self-Organised Criticality is characterised by
• Continuous Change
• High Sensitivity to External
• conditions
• Events on all Scales

http//www.sst.ph.ic.ac.uk/kim/research/rice.html
4
Self-Organised Criticality

• Some indicators
• Regular distribution of catastrophic events
• 1/f noise
• FRACTALS

5
Fractals

• Self-Similarity

http//vortex.plymouth.edu/clouds.html
6
Fractals

• Non-linear dimensions
• 1 D
• 2 D
• 1.54 D ??

http//classes.yale.edu/math190a/Fractals.html
7
The Picture
http//www.ghcc.msfc.nasa.gov
8
Fractal Analysis
9
Fractal Analysis
10
Fractal Analysis
11
Fractal Analysis
12
OBEYING A POWER LAW
13
Finding the dimension

• 1 - D gradient of line
• D 1.1
• NOT AN INTEGER!

14
Do All clouds have fractals???
15
D 1.4
D 1.4
16
PERIODICITY IN CLOUDS
PART 2

• An insight into MATLAB and its errors

17
Fourier Transform
18
Acknowledgements

• Per Bak, How nature works, 1947
• Neeraj Sharma, for sharing his ideas and results
• Iver Cairns for guidance
• Matlab
• People who listened to
• me whinge about Matlab