1. The global atmospheric electric circuit – an overview
Corte, 27 June
Corsica, 2008
Workshop on Coupling of Thunderstorms
and Lightning Discharges to Near-Earth Space
The global atmospheric electric circuit – an overview
Michael J. Rycroft1 and Anna Odzimek2
1CAESAR Consultancy, 35 Millington Road, Cambridge CB3 9HW, and
Centre for Space, Atmospheric and Oceanic Science,
University of Bath, Bath BA2 7AY, U.K.
2Department of Physics and Astronomy, University of Leicester,
University Road, Leicester LE1 7RH, U.K.
“What the imagination seizes as beauty must be truth”
John Keats, poet ( )
“Imagination is the highest kite one can fly”
Lauren Bacall, actress (1924-present)

2. ATMOSPHERIC STUDIES FROM THE INTERNATIONAL SPACE STATION
Corte, 27 June
Corsica, 2008
Workshop on Coupling of Thunderstorms
and Lightning Discharges to Near-Earth Space
ATMOSPHERIC STUDIES FROM THE INTERNATIONAL SPACE STATION

3. SCHEMATIC DIAGRAM OF THE GLOBAL ATMOSPHERIC ELECTRIC CIRCUIT
Corte, 27 June
Corsica, 2008
Workshop on Coupling of Thunderstorms
and Lightning Discharges to Near-Earth Space
SCHEMATIC DIAGRAM OF THE GLOBAL ATMOSPHERIC ELECTRIC CIRCUIT
Ionosphere
Atmosphere
Earth’s land/
Ocean surface
Rycroft and Fullekrug, JASTP, 2004, Fig. 1

4. Corte, 27 June
Corsica, 2008
Workshop on Coupling of Thunderstorms
and Lightning Discharges to Near-Earth Space
EARLIER ELECTRIC REPRESENTATIONS OF THE GLOBAL ATMOSPHERIC ELECTRIC CIRCUIT
Kasemir, 1965
Markson, 1978
Makino and Ogawa, 1984
Nisbet, 1983

5. Rycroft et al., JASTP, 2000, Fig. 5 Corte, 27 June
Corsica, 2008
Workshop on Coupling of Thunderstorms
and Lightning Discharges to Near-Earth Space
Rycroft et al., JASTP, 2000, Fig. 5

6. Tinsley and Zhou, JGR, 2006, Fig. 2
Corte, 27 June
Corsica, 2008
Workshop on Coupling of Thunderstorms
and Lightning Discharges to Near-Earth Space
Tinsley and Zhou, JGR, 2006, Fig. 2

7. DISTRIBUTION OF POTENTIAL AROUND THUNDERCLOUD
Corte, 27 June
Corsica, 2008
Workshop on Coupling of Thunderstorms
and Lightning Discharges to Near-Earth Space
DISTRIBUTION OF POTENTIAL AROUND THUNDERCLOUD
Rycroft, In Fullekrug et al. book, 2006, Fig. 2

8. Rycroft et al., JASTP, 2007, Fig. 2 Corte, 27 June Corsica, 2008
Workshop on Coupling of Thunderstorms
and Lightning Discharges to Near-Earth Space
Rycroft et al., JASTP, 2007, Fig. 2

9. Rycroft et al., JASTP, 2007, Fig. 12; EGU 2008 poster, Fig. 1
Corte, 27 June
Corsica, 2008
Workshop on Coupling of Thunderstorms
and Lightning Discharges to Near-Earth Space
Rycroft et al., JASTP, 2007, Fig. 12; EGU 2008 poster, Fig. 1

10. FAIR WEATHER REGION Rycroft et al., JASTP, 2007, Fig. 15
Corte, 27 June
Corsica, 2008
Workshop on Coupling of Thunderstorms
and Lightning Discharges to Near-Earth Space
FAIR WEATHER REGION
Rycroft et al., JASTP, 2007, Fig. 15

11. CARNEGIE CURVE AND THUNDERSTORMS
Corte, 27 June
Corsica, 2008
Workshop on Coupling of Thunderstorms
and Lightning Discharges to Near-Earth Space
CARNEGIE CURVE AND THUNDERSTORMS
Williams, Global electrical circuit, Encyclopedia of Atm. Sciences, 2002, Fig. 3

12. CARNEGIE CURVE AND NUMBER OF LIGHTNING FLASHES (OTD DETECTOR)
Corte, 27 June
Corsica, 2008
Workshop on Coupling of Thunderstorms
and Lightning Discharges to Near-Earth Space
CARNEGIE CURVE AND NUMBER OF LIGHTNING FLASHES (OTD DETECTOR)
Nickolaenko et al., GRL, 2006, Fig. 4

13. DIAGRAMMATIC LIGHTNING DISCHARGES (IN RED)
Corte, 27 June
Corsica, 2008
Workshop on Coupling of Thunderstorms
and Lightning Discharges to Near-Earth Space
DIAGRAMMATIC LIGHTNING DISCHARGES (IN RED)
Altitude [ km ]
Williams et al., JGR, 2006, Fig. 2

14. -CG PRODUCING STORM +CG PRODUCING STORM
Corte, 27 June
Corsica, 2008
Workshop on Coupling of Thunderstorms
and Lightning Discharges to Near-Earth Space
-CG PRODUCING STORM
+CG PRODUCING STORM
Rycroft et al., JASTP, 2007, Fig. 13

15. IONOSPHERIC POTENTIAL AFTER LIGHTNING DISCHARGES
Corte, 27 June
Corsica, 2008
Workshop on Coupling of Thunderstorms
and Lightning Discharges to Near-Earth Space
IONOSPHERIC POTENTIAL AFTER LIGHTNING DISCHARGES
Odzimek and Rycroft, EGU 2008 poster, Fig. 2

16. SPACE-TIME REGIONS AFTER CG DISCHARGE WHERE BREAKDOWN FIELDS EXCEEDED
Corte, 27 June
Corsica, 2008
Workshop on Coupling of Thunderstorms
and Lightning Discharges to Near-Earth Space
SPACE-TIME REGIONS AFTER CG DISCHARGE WHERE BREAKDOWN FIELDS EXCEEDED
Odzimek and Rycroft, EGU 2008 poster, Fig. 3

17. Odzimek and Rycroft, EGU 2008 poster, Fig. 4
Corte, 27 June
Corsica, 2008
Workshop on Coupling of Thunderstorms
and Lightning Discharges to Near-Earth Space
Odzimek and Rycroft, EGU 2008 poster, Fig. 4

18. Odzimek and Rycroft, EGU 2008 poster, Fig. 5
Corte, 27 June
Corsica, 2008
Workshop on Coupling of Thunderstorms
and Lightning Discharges to Near-Earth Space
Odzimek and Rycroft, EGU 2008 poster, Fig. 5

19. Corte, 27 June
Corsica, 2008
Workshop on Coupling of Thunderstorms
and Lightning Discharges to Near-Earth Space
CONCLUSIONS
We must strive to understand better all aspects of the Earth’s atmosphere, and how it responds to both external and internal influences (feedbacks).
An electrical engineering - software - model of the DC global atmospheric electric circuit, with 1 km vertical resolution, has been constructed; it uses a realistic model of the height profile of atmospheric electrical conductivity.
The currents generated by thunderstorms and electrified shower clouds contribute about equally (~ 500 A each) to maintaining the positive potential (~ 250 kV) of the ionosphere with respect to Earth (both good conductors).
Lightning does not contribute very significantly (i.e. only ~1%) to maintaining the high potential of the ionosphere, because the effects of and – cloud-to-ground (CG) discharges essentially cancel each other out.
+CGs with significant continuing currents can lead to “carrot” sprites, whereas +CGs with only a return stroke can lead to “column “ sprites.
The increased conductivity of the mesosphere (10-7 S/m) associated with a sprite decreases the ionospheric potential by only ~1 V more than for a +CG which is not followed by a sprite.

20. THANK YOU – ANY QUESTIONS?
Corte, 27 June
Corsica, 2008
Workshop on Coupling of Thunderstorms
and Lightning Discharges to Near-Earth Space
THANK YOU – ANY QUESTIONS?
News on 7 May 2008:
Hot night in Chile: dust and ash from the eruption of the Chaitén volcano explodes into the night sky as an electric storm passes overhead
(News, page 27)
Photo from