Partly I was wanted the challenge of making instruments work,
as well as trying to study
the chemistry of the earth, I wanted to make sure I could do something that
had to do with constructing instruments and so I built a device to make the
measurements of the concentration of carbon dioxide that was called a
manometer
and a manometer, I found by reading in the literature something that had been
built a long time earlier
and I made some changes because there was
new technology, better ground, last stop cocks and so on,
and particularly liquid nitrogen was available,
liquid nitrogen being something like which I could freeze out the
carbon dioxide rather than do it
the way it was being done in Scandinavia, where they were
absorbing it in a caustic solution and then trying to release it from the
solution and that was chemical method which was not as precise as the one I had
so with this precise manometer and the use of liquid nitrogen, I was able to make
these measurements quite accurately.
So now I compared these measurements with what was going on in Sweden
and I found that it was, they weren't concordant and I had an opportunity
to take some of these,
well, I haven't told you the device itself. It was a
glass vessel, about this big around,
and it had a a closure at the top
so I could actually pump the air out of it
and make it a vacuum and then all they had to do was to turn a little
delve on the top, stopcock it's called
and the air would go, it comes out in the flask and then you would close the stopcock
and you could send it anywhere.
I was very fortunate that as I was doing this work,
there was an internationally organized program
to study geophysics, particularly
the ionosphere,
for radio propagation but it was in large to be a much more ambitious
program
and it allowed
for exploration in many different ways, including
oceanographic ships going out all around the world
and setting up locations to big measurements. We would call these
observing stations and I got a chance
to join this program. It was called the International
Geophysical Year and this wasn't so long after World War II. It was 1957 when
it actually occurred in the
beginning of the planning that I got involved with was 1956, one year after I
made this discovery about our measurements being different and
people's measurements made by in other places
by different techniques. So I was
given a chance to join this program and even though
to get back to the fact that I was not very old yet I was about 26 years old
when this started,
that I had this opportunity to command
the samples be taken in quite distant places including the South Pole
and ice flows in the Arctic Ocean.
Now that's really an opportunity which could not come very often
and so the beginning of the International Geophysical Year we,
we send some samples to a lot of different places, as I just described as,
also tropical locations,
and they all came back with nearly the same result. In fact it was so much
the same result that when they were
published in a bulletin of the International Geophysical Year,
which was coming out to let people know what happened, somebody said it
it must be that the instrument I was using was stuck.
And it was just making the same measurement all the time
but of course we checked that out it, and it wasn't true and
so, we went ahead and kept taking these measurements.
And part of the program
came about because I was invited to go to the
United States Weather Bureau which had an office of
meteorological research. It wasn't a very big
organization but it did have
a chance to take part in this International Geophysical Year
so I went to the director at his invitation and told him about what I was
doing.
I showed him some of my measurements and he said,
"We have just recently set up an observatory up on a mountain in Hawaii
and this would be a wonderful place to make these measurements." And he was very
ambitious to get this station
to be more recognized by doing as many things as they could,
and so he supported the idea of going out there and not just measuring it
by taking a sample now and then, in a bottle and bringing it back but putting an
instrument that it would measure continuously.
And meanwhile I had found a
company in Pasadena, California.
This company had an instrument and so they lent
me an instrument and I was able to test it out and find out that it was probably
good enough to make these measurements.
And so, because of the International Geophysical
Year, I was able to buy them. So it was expensive
and yet we were able to buy four of these estimates. We put one on a ship, we put
one in
the Antarctic. We put one at Mauna Loa Observatory and
we kept one for ourselves, to be able to see how they worked
and that launched the program of making continuous measurements
and the Mauna Loa Observatory began the measurements in 1958.
It took nearly the end of the International Geophysical Year period before it got
started
but once it was there, itwas clear was going to make some interesting
results.
What I was trying to lead up to was that the concentration variation that we meant
measured at Mauna Loa observatory was about six parts per million
between summer and winter and that was within the air
bar, the air of what the measurements were being made in
Scandinavia
and so they couldn't detect it, but it
could have been detected long before that if
they had been more diligent about checking the
precision of what they were doing so
we found that it was indeed varying with the seasons but the other
remarkable thing was that
we found that as we trace it into the second year,
it was a little bit higher, and by the third year, it
was quite clear that it was going to be higher each year
at least it was being higher each year than it was before for the same time of the
year.
So we were getting an increase from year to year and
it didn't take that many years because it was going up by
nearly a part per billion per year, so we had to have that precision of better
than one part per million
but with that precision we saw that it was trending upward as well as
oscillating between the seasons.