Cloud physics research
One year ago . . .
Ice age epochs on the earth may result from our solar system's trek
through the spiral arms of the Milky Way. Nir Shaviv
(shaviv@..., +972-54-738555), of the University of
Toronto and Jerusalem's Hebrew University bases this hypothesis on
correlations he has found between apparent changes in the flux of
cosmic rays reaching the earth and geological evidence for major ice
ages in the past billion years.
. . .
Fangqun Yu, a research associate with the Atmospheric Sciences
Research Center at the State University of New York-Albany, has shown
that cosmic rays may have height-dependent effects on Earth's
cloudiness. Yu's National Science Foundation supported study is
published in the July 2002 issue of the American Geophysical
Union's "Journal of Geophysical Research-Space Physics."
Cosmic rays are comprised of energetic particles, mainly protons,
originating from all directions in space, from both solar and non-
solar sources. A distinction can be made between solar protons (SP)
with relatively low energy levels (10-300 MeV) and GCR with higher
energy levels (300MeV to 10GeV). The solar wind has a strong role in
modulating cosmic ray intensity (Yamada et al., 1998). In particular,
at short time scales, irregular decreases of GCR intensity, known as
Forbush decreases (FD), can be observed. FD events are associated
with magneto-hydrodynamic disturbances following solar coronal mass
ejections (Krivsky and Ruzickova-Topolova, 1978, Reiter 1992).
Upon entering the magnetosphere cosmic ray particles are influenced
by the Earth's magnetic field and the configuration of the
magnetosphere. As the cosmic ray particles enter the atmosphere they
collide with other atmospheric particles. Cosmic rays are the
principle cause of ionisation in the lower atmosphere, which peaks at
a height of 10-20km in the atmosphere. It has been suggested that
cosmic ray ionisation has direct and indirect impacts on cloud
microphysics (Dickinson, 1975; Tinsley and Deen, 1991; Tinsley et
al., 1989). GCR may directly influence cloud through the production,
via cosmic ray ionisation, of cloud condensation and/or ice nuclei.
Indirect mechanisms include modulation of the atmospheric electrical
conductivity within the 'global electric circuit' by GCR ionisation
and subsequent effects on cloud microphysics through the process of
electro-scavenging (Tinsley et al., 2000). Tinsley et al. (2000)
showed greater scavenging rates for charged evaporation aerosols in
non-thunderstorm clouds compared to non-charged aerosols. A further
indirect mechanism has been proposed in which GCR ionisation
influences nitrous oxide and ozone production and thus stratospheric
heating rates. This alters the stratospheric and tropospheric
circulation and possibly the cloud distribution (Brasseur and
Solomon, 1995). Through both direct and indirect processes it is
hypothesised that an increase (decrease) in GCR should result in an
increase (decrease) in cloud, greatest for high clouds and at high
geomagnetic latitudes where transmission of the cosmic ray flux is at
its maximum. FD events have been associated with a decline in high
cloud at high latitudes of the northern hemisphere (Pudovkin and
Of course, none of this work contemplates the impact of the biosphere
on these EMF/cosmic ray forcings to clouds
- This is vert interesting, Mike! Let me run this past you. A more
active sun means a more energetic and denser solar wind. On a solar
system-wide scale, this will serve to expand the sun's heliosphere,
and also to provide something of a shield against incoming extra-solar
cosmic rays. Conversely, an inactive sun will allow more cosmic rays
to penetrate deeper into the solar system, and therefore reach Earth.
According to the article, more cosmic rays means, at least
theoretically, more clouds.
So, an inactive sun could have a double-whammy on Earth's climate!
One, decreased solar energy output will obviously mean less energy
getting to Earth. That means cooling for Earth. Now, we can possibly
add in the effect of more cosmic rays meaning more cloud cover, which
will further reduce the amount of solar energy reaching the Earth's
surface. More cooling! One could easily see how an extended period
of solar inactivity could lead to an ice age!
I just wish I could give you years of biological education in a
paragraph or two, but I would have to disagree again with your
characterization. Understand this isn't about hot and cold but about
MODULATED hot and cold. IOWs if I put you in a heated room your body
temperature stays at 98.6 degrees--and you sweat. But if you catch a
cold your body temperature rises.
What the cosmic rays would do is increase the protons to ground and
how the ocean terresphere EMF balance is modulated by the biosphere.
Once an area is frozen the hydrology ends and so do river feedbacks.
IOWs what we are talking about is the RISK of putting a neo glacier
on and how long it takes for the sun to melt it back without
precipitation replacing it.
This is why we see storms w/ the elevated PROTON wind. But that
doesn't mean that these storms are not modulated by the biosphere and
the EMF control it exerts . . .
So it again comes back to feedback loops and DEFECTS in them by a
fossil fuel subsidized culture--or a culture that messes w/ its
hydrology, and therefore the modulating biosphere in the deltas of
this hydrology . . .
--- In firstname.lastname@example.org, "David" <b1blancer1@e...>
> This is vert interesting, Mike! Let me run this past you. A moresolar
> active sun means a more energetic and denser solar wind. On a solar
> system-wide scale, this will serve to expand the sun's heliosphere,
> and also to provide something of a shield against incoming extra-
> cosmic rays. Conversely, an inactive sun will allow more cosmicrays
> to penetrate deeper into the solar system, and therefore reachEarth.
> According to the article, more cosmic rays means, at leastpossibly
> theoretically, more clouds.
> So, an inactive sun could have a double-whammy on Earth's climate!
> One, decreased solar energy output will obviously mean less energy
> getting to Earth. That means cooling for Earth. Now, we can
> add in the effect of more cosmic rays meaning more cloud cover,which
> will further reduce the amount of solar energy reaching the Earth's
> surface. More cooling! One could easily see how an extended period
> of solar inactivity could lead to an ice age!