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a chain of physical processes of ionization of air molecules. This

primary sequence leads to two major consequences: change of the air

conductivity and, consequently, change in the near ground atmos-

pheric electric field, which includes latent heat release. A second

phenomenon, known as the ‘thermal branch’, has been established by

the scientific community only recently with the increase in measure-

ments of surface temperature in different bands of infrared emissions

detected by NASA and NOAA satellites.

One of the important components of utilizing thermal remote-

sensing data (NASA’s Terra and Aqua, NOAA’s GOES and POES) is

analysis of the continuous outgoing long wave earth radiation (OLR),

which indicates anomalous variations prior to a number of medium

to large earthquakes.

OLR energy has been measured at the top of

the atmosphere by NASA and NOAA satellites and includes emis-

sions from the ground, atmosphere and cloud formation. We have

been using NOAA/AVHRR IR daily and monthly (two and half

degree) gridded data to differentiate between global and seasonal

variability and the transient local anomalies.

This phenomenon has been linked theoretically as part of a rela-

tionship between tectonic stresses, electrochemical and

thermodynamic processes in the atmosphere and increasing Earth

radiation emission, all part of a family of EM phenomena related to

earthquake activity. The timescale of the observed variations is a few

days, seen a week or more before the onset of the seismic event. In

comparison with several years of data, the observed time series

preceding the earthquake had unusually high OLR. The OLR anomaly

corresponds to a large area of ground coverage and coincides with

the main epicentral zone. We explored the significance of these obser-

vations for the two most devastating events on the Asian continent,

the M7.6 Kashmir earthquake of 8 October 2005, and most recently

the Mw 7.8 earthquake in Eastern Sichuan, China on 12 May 2008.

In the case of the Kashmir earthquake, compared to the reference

fields for the months of December 2005, 2006 and 2007, we found

OLR anomalous fluxes of the order of >32 W/m

, with an absolute

value of 282 W/m

along the epicentral area beginning 4 October,

four days before the event. Maps of daily night-time thermal infrared

(TIR) anomalous (mean field defined for three years 2005-2007) of

Earth outgoing radiation (NOAA18/AVHRR, 1:38 a.m. mean local

time) over Kashmir/Pakistan region for 5-8 October are

presented below. Tectonic plate boundaries are shown

with a red line, with major faults in brown. Red stars are

earthquake epicentres, red circles – 0.5 pixel area. A

monthly time-series graph for the daily night-time OLR

variations – for 25 September-25 October 2008 over the

pixel nearest to the epicentre (35N/72.5E) area – reveals

some pre-event (in red) and post-event aftershock activ-

ities (in green).

In the case of the Eastern Sichuan earthquake, the

NOAA-18 OLR survey for April-May shows that the

initial indication of building an atmospheric anomaly

was detected on 5 May (five to six days before the main

shock) and the maximum reaches the value of 20 W/m

westward from the epicentre. The OLR reference field

was built for the entire period of 2005-2007. During the

period of 6-9 May, strong OLR anomalies were building

near to the epicentral area, over the major fault lines

with the highest value of 38 W/m

. These are most likely

connected with the gas release enhancement and addi-

tional flux emission, and provide information about

major fault activation in this area.

In summary, through our research we have found a

significant relationship between solid Earth actions and

atmospheric and ionospheric coupling. This relationship

has been studied by a number of scientists with impor-

tant results, but more work in this area needs to be done.

It is not a trivial effort and will require many more years

of research before such an application should become

important for earthquake prediction. NASA’s role in this

research is clear in that the agency has a history of explo-

ration into the unknown. We hope that this work will

eventually provide significant early warning for such

catastrophic events as the recent earthquake in China. It

is with this in mind that NASA will continue to support

this and other methods of monitoring and early detec-

tion of Earth movement, such as GPS and InSAR, to

provide societal benefit to the nation and the world.

Monthly maps of OLR around the time of M7.8 Sichuan earthquake of 12 May, 2008

(1) a month before (1-30 April), (2) during (1-31 May) and (3) after (1-30 June) the M7.8 12 May, 2008 earthquake (reference field for 1980-2008),

(tectonic plate boundaries with red line, and major faults with brown color, red stars – earthquake epicentres, red circle – 0.5 pixel area)

Source: Ouzounov D., S.Pulinets, M.Parrot, P.Taylor, S.Habib, H.C. Wu, J. Ma, C.I-Wan Atmospheric and ionospheric signals associated with the Eastern Sichuan, China M7.8

earthquake of 12 May 2008 revealed by multi sensor space and ground observations, 2008, (in preparation)