Cosmic Rays, Global Warming and the Origin of life.

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Cosmic Rays, Global Warming and the Origin of life. Sir Arnold Wolfendale FRS, 14 th Astronomer Royal. Topics to be covered. 1. Low Cloud Cover and the CR correlations. 2. Lightning. 3. Origin of life. Low cloud cover anomalies and CR intensity (Huancayo) – Svensmark (2007). - PowerPoint PPT Presentation

Transcript of Cosmic Rays, Global Warming and the Origin of life.

Cosmic Rays, Global Warming

and the Origin of life.

Sir Arnold Wolfendale FRS, 14th Astronomer Royal.

Topics to be covered.

1. Low Cloud Cover and theCR correlations.

2. Lightning.

3. Origin of life.

Low cloud cover anomalies and CR intensity(Huancayo) – Svensmark (2007)

There is a correlation – in time – between ‘cloud cover’, at low altitudes, and ‘cosmic ray intensity’.

Is it a case of ‘cause and effect’?

Cosmic ray ionization

Charged cosmic rays produce

ionization.

Although unlikely, CR ions help the

growth of cloud nuclei by attaching to

aerosols.

Check, first, by examining the cloud

cover – CR correlation over the earth.

Earth’s magnetic field causes a

variation of CR intensity over the

surface of the earth.

Correlate with CR intensity or sun-

spot number.

Ions as condensation centres for clouds ?

But

Supersaturations in atmosphere far too low for ions to be at an advantage. Aerosols (salt particles, dust, industrial emissions…) dominate.Sizes 10-1(10±2).~~

CR produce ~ 3 ion pairs cm-3s-1 in the lower atmosphere. Lifetime is ~ 50sec, so ~ 150cm-3.Clouds have ~ 100 droplets cm-3 so a link would appear to be obvious.

Evidence from radioactive ‘events’

Chernobyl

~~

~

April 26, 1986 2 Mt of fall-out.No increase in cloud cover.(ions cloud droplets) 3%

Nuclear Bomb Tests

E.g. BRAVO -Bikini Atoll, March1,1954.~ 15 Mtradioactive particles,10 -100

300 miles from Ground Zero, dose rate ~ 100 Rh-1, after 4 days. Yields 5.107 ions cm-1s-1

Averaging over space and time and allowing for size distribution yields.

10-4<~

Radon

Radon is an important contributor to atmospheric ionization over land.

Indian ‘hot spots’, particularly in the SW.

Scans of low CC over two regions show no excess and

25%<~

Dorman’s rigidity map

Magnitude of the CC modulation vs. VRCO

1. Cosmic Rays

a. LCC directly (difficult)

b. Effect on atmospheric transparency – ht. ~10km (aerosols.) Kudryavstevetal,(2005)

c. Electrical effects. CR affect the ‘global atmospheric circuit’ (Tinsley, Harrison, Rycroft…). Cloud edges?

Possible explanations for the correlations – i.e. the 11 – year

cycle.

Global mean Surface Temperature:

peak to peak 0.07oc for change in radiation of 0.24Wm-2

Mt. Pinatubo Volcano (1991)

Temperature reduction 0.8 deg C. year

Change in radiation of 3.6 Wm-2 year

A similar ratio (but energies very different):

Pinatubo 1016J; oceanic change 2.1022J, - a factor of 1 million.

Also problems with 22y/11y conversion and geographical distribution of temperature change for 11-y cycle.

2. Solar Irradiance

The ‘atmosphere’

Tentative Conclusions

3. Solar irradiance variations probably cause the solar cycle (11-year) oscillation.

2. CR contribution to slow increaseof mean global temperature overlast 35 years < 1%.~

~

1. CR contribution to 11-year cyclevariability of mean globaltemperature < 15%.

Summary for decadal averages

“Man made Global Warming”

“Man made Global Warming”

Global and continental temperature change

Man –made

Response

Imbalance

Total

Natural

Aerosols

Ozone

CO2

F2: Percentage cloud changefor a 2% change in CR intensity

Possible ‘natural causes’ of Global Warming

1. Cosmic Rays

2. Solar Effects

3. Milankovich Effects

4. Geothermal Changes

5. Volcanoes

6. Meteoritic and Cometary Dust

7.Oceanic Heat Re-distribution

8. Past ‘random’ changes. (10,000 y ago)

Lightning

Miller (1953) – and Miller & Urey

water, methane,ammonia, etc.(the ‘pre-biotic soup’)

Amino-acidsRNAMonomers

SNR Model : A.D. Erlykin & AWW (2001)

On average, every million years,

ICR(>1016eV) up by ~ 105 for ~

30,000 years.

Probably enough to cause a

sufficiently large frequency of

lightning discharges to cause

production of RNA, monomers,

etc. in the window : 4.5 – 3.5 By BP.

After Parman (2009)

More recently – and more

probably – the generation

of NOX by lightning will

have had relevance to

evolution.

NOX is welcome to plants

and bad for humans.