🚀 go-pugleaf

Greig Ebeling wrote:

> >Surface measurements of UV also show upward trends over later
> >decades.
 
> There is some speculation regarding the relevance of this, considering
> that UV increases are greater in high lats, where natural UV levels
> are low, and also that higher surface UVR does not necessarily
> translate into higher exposure, considering sunwise trends, and
> blockout.

That's why the proposed research, I reffered to, is needed.
 
> >Given that early exposure to UV has been linked to increased
> >incidence of skin cancer in later life - it is reasonable to
> >guess that these trends may be correlated.
 
> Actually it is far more likely that it was caused by the suntanning
> trend of the late 60s and 70s.  This is obvious from the fact that
> skin cancer has a long latency period.  Also, ozone depletion has only
> occurred at a significant degree in the last 10 years.  Any
> correlation between UV-B exposure and increases in cancer would need
> to show a recent increase. This is not shown in the data I have seen.

I agree that the suntanning trend may, so far, be the most important
factor in increased incidence of skincancer in Australia, however
there may also be a component due to increased UV surface flux.

I re-iterate the questions that I understand the Meteorology CRC
research to be addressing. I think you will find that they try
to remove some of the speculation concerning the relavance of
increasing UV flux to increasing melanoma incidence.

"Are there spatial/temporal correlation between the observed
UV surface flux and the observed skin cancer incidence?"

ie. are there any statistical correlations between the data
time-series for surface UV flux and the time series for skincancer
incidence? If so, can we measure the latency or lag?

"If so how much of the increasing skin cancer incidence is due 
to environmental rather than behavioural factors?"

ie. can we estimate how many more skincancers we will get in future
if behavioural patterns remain unchanged.

Just as an aside, perhaps human skincancer is not the best medium
for detecting increasing UV damage to biological systems. Maybe
we can find a plant or animal that cannot "slip,slop,slap" with
measurable UV effects.

Any suggestions?

fred

http://www.shm.monash.edu.au/~f.pribac