— ee eee

ber: it once again stands head and shoulders
above the rest, for the period from September to

January, especially when it comes to record .

precipitation falls and a distinct lack of bright
sunshine,

In: Figure 3. we compare the average
annual temperature structure for the periods
(1978-1984) and (1985-1991) with the 1951-
1980 normal temperature structure.

As we compare the evidence in Figure 3.,
we see that period one was warmer than nor-
mal, which is not too surprising with 1982-83,
an El Nino year, being included. Period two
was even warmer yet, and again this is not
surprising since there appear to have been two

El Nino periods, 1988-89 and 1991. Perhaps, |

though, this is too simplistic; could we really be
looking at a major warming trend?

Certainly those who expect to see evidence
of the so-called Greenhouse Effect might think
so, but a word of caution: we have had warming
and (of course, cooling) trends before and will
likely see similar trends in the future. For as
one wise man said, “There is nothing new
under the sun... what has been done, will be
done and what has happened before will hap-
pen again."

normal with snowfall being near normal but
quite wet as is noted once again from the water
curve. Thus, the total precipitation for the
second period was well above normal. In fact,
the second period was wet enough so that the
average of the two periods was slightly above
normal.

MMM 1951-1980 average
[™"] 1978-1984 average
WMA 1985-1991 average

Minimum
FIGURE 3.

Maximum

1985-1991 with the 1951-1980 Normal

_ Mean

Comparison af the temperatura structure of the periods 1978-1984 and
Structure.

Finally, and perhaps the most important
thing in the minds of many, there has been a
steady increase in the hours of bright sunshine!

Some of the simpler conclusions are that it
has been getting warmer and sunnier

MMM 1951 - 1980 average
1976 - 1984 average
HH 1985 - 1991 average

==
RAIN (mm)

FIGURE 4.

Comparison of the precipitation and sunshine structures for the periods
1978-1984 and 1985-1991 with the 1951-1980 Normal Structure

aver the last 14 years, It has also

would expect with warmer tempera-
tures, more of our precipitation has
been in the form of rain and less in
the form of snow.
But is that all we can conclude?
As we mentioned earlier in this
report, we have had warm spells
before; yes, we have even had wet
spells before. As for bright sunshine,
we will all agree, I am sure, that we

wULIY SSSA

Figure 4. compares the average annual
precipitation structure as well as the hours of
bright sunshine structure for the same periods
charted in Figure 3.

As we compare the evidence in Figure 4.,
we see that week one had near normal rainfall
but much less snowfall than normal and as a
result there was below normal precipitation for
the first period (1978-1984). We note too that
the snowfall during the first period was quite
dry as depicted by the curve labelled “water”,
which indicates the water equivalent of the
snow. |
Period two, however, was a different story
in most respects. Rainfall was much above

will take all we can get up here in
the Great Northwest.

And so, are we looking at evi-
dence of Global warming? We simply do not
know!

In conclusion all we can say is that 1978,
the Year of the Great Flood, was a year to
remember; 1982-83, an El Nino year, was
another year to remember; and 1988-89 was
also an El Nino year to remember. 1991, is, in
the history available to us, a year among years
to remember. Hopefully it is the culmination of
this period of very warm, wet years and not a
harbinger of things to come.

— Compiled and written by Harry F. Earle.
Edited by Adrian Van de Mosselaer
and John How

Terrace Weather Office, Terrace, B. C.

Terrace Review — March 6, 1992

been wetter overall and, as one