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November 13, 2007
I came across this quote in The Economist the other day. There are places in Australia which is one
of the ‘bread baskets’ in the world and in some places it hasn’t rained in 13 years. This one farmer in
New South Whales had a little rain so he borrowed money to plant his crop and now he has a
problem. There is no rain and that is devastating.
Also I checked the weather network the other day and they have something called ‘Climate Change’
and it is put up by David Suzuki. He has an interesting analogy and I suggest you take a look at it. It
says that the evidence is overwhelming that climate change is happening. It say that we are all in a
car and heading for a brick wall and the car is speeding up and the point is that everyone in the car is
arguing about where they are sitting. He says that it doesn’t matter because everyone is going to hit
‘An Inconvenient Truth’ is the article by Al Gore and they say he shouldn’t run because it shouldn’t
mix with politics. Everyone wants someone else to pay for the problem.
Second part of biological impacts of climate change.
How will the changing greenhouse gasses and climate warming affect the climate? We talked about
CO2 levels and how they will affect plant communities. It won’t have major effects as of yet. It is an
urgent question. Remember on the earth’s planet we are not the only species, there is an estimate of
about 30 million species.
If we look at the complexity of the problem climate change is only one of five variables that affect the
impact of humans on the world. Here you see the human population and remember it isn’t just the
size (6.6 billion) or how many humans are here but it has a major effect on the limited world. This is
a problem i.e. water. Per capita we consume much more than people in the third word. Human
enterprises like agriculture and industry have a major impact. There is a major oil spill in the Caspian
this week. Recreation also has an affect i.e. like ATV’s are ruining the environment. In Norway
nobody can own a ski doo unless it is for work. So our human enterprises changes the land, there is
massive land transformation. When I was a kid I thought that the Boreal forest wouldn’t change but
it has. If you ever fly to Vancouver and you go across the 49th parallel north is ranch land and south
the Americans are growing crops and they shouldn’t be planting there because extreme amounts of
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We talked about the gasses and that changing. Biotic additions and losses i.e. invasion like the Zebra
Mussels, hunting, and fishing. They are all interconnected to the loss of biological diversity. So is
climate change responsible? Clearly sometimes it is. It is very interconnected in relationships. We
have extinction of species and populations. If the species survives but they lose genetic material that
is no longer part of the potential evolutionary framework for that species.
Changes in Biological Systems
There are 6 areas that we will tackle in terms of trying to observe the signatures of climate change.
1. Phenology – changing in timing of many life cycle events. When plants bloom and animals
2. Range – animals and plants are ranging further north/south of the equator.
3. Abundance – obviously it can go up and down.
4. Differential change – here you get the real problem because if species are closely attuned to
each other there is evolution but if you move away and emerge later I have a problem. There
is a mismatch in individuals in the community and that can change relationships.
5. Extinction or expiration
6. Changing morphology, reproduction, or genetics
I will throw out numbers but I will emphasize the numbers that you need to know. The ideas behind
them are important and the examples in some sense but the numbers are overwhelming so you won’t
remember all of them. Is this going to be on the exam? Yes…maybe, but the other numbers won’t
This evidence is form Germany. The important things are temperature in Mar/Apr and
Mar/Apr/May. Temperatures are changing. Then you can ask; how does that affect phenology?
Note the negative numbers, this means things are happening earlier. It gives anomaly in terms of
days and temperature. Things are getting warmer and happening earlier.
Mean spring passage (birds) when they migrate through this place, Helgoland. We have Flycatchers
here and this is the orange line. Unfolding of the Horse Chestnut tree. We have these trees here.
Then we have the leaves unfolding on the Birch earlier. This type of evidence, remember the critical
thing is long term in monitoring or you wouldn’t know what was going on. The government has
decided that we will get rid of wildlife research and everything will go to global warming! Some
idiot thought this wouldn’t be linked to global change but it isn’t a government priority! Do they
have any brains?
By far most of the climate change responses have been in species phonologies. There are tight links
between seasons and agriculture. Some of the earliest dates for phenology they come from a planting
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and harvesting dates. Then the associated changes with climate. They have been recorded backwards
for 100’s of years. Oddly, I don’t know why people in N. Europe have this inclination but they say
that people from other countries have been keen on recording the first signs of spring. Spring is
important. The sun is disappearing and for many of us we are sad about that. In Norway spring
would come and everyone would sit out on benches to observe the sun. Anyone have SAD? It is
directly related to melatonin and phenology. The longest records of direct observations come from
observing blooming of Cherry blossoms in Japan. This goes back 600 years. Apparently they look at
this evidence and they first saw significant changes around the year 1900. Note that just outside these
walls the Japanese Government gave us Japanese Cherries so look at them next spring. Same deal
with the grape harvest. If you look at France April to August explain 84% of the variation of when
grapes are harvested. This is fundamental to these people. The heat wave of 2003 was the warmest
summer for 500 years and many people died. Most observations are 30 -> 50 years though.
Critical number: (based on Meta analysis – people gather together and put together different
studies and decide on something) the bottom line is that for every 1C degree increase there is
advancement in spring of 1 -> 12 days. The Meta analysis indicates that average values for
phonological species are between 2.5 and 6 days per 1C degrees. That is the average not the
Critical number: In terms of predicting every 10 years is it increases by about 2.3 to 5.2 days
The bottom line is that there is a clear temperature driven extension of the growing season by up to 2
weeks in the mid to late 20th century. It is mostly due to earlier springs and maybe a little to do with
earlier Autumn/fall. Potentially it will increase the length of the frost free season. If it looks at
Canada the length of the frost free season determines what we can grow. In the Prairies a short frost
free season is a limitation in growing wheat and that is the prime crop. T hey had to develop strains of
wheat that matured earlier and earlier. It also affects productivity which should be enhanced by a
longer frost free season. There is an analysis done to look at how the growing season changed and
they bisected the continent into 2 zones and the bottom line is since 1966 the growing season has
increased only in the 4 coldest most northerly zones (in the U.S. from 42 to 46 latitudes). They
expect them to occur at the higher latitudes and that makes sense to the picture we have of latitude
changes. We look at Europe and the growing season from 1959 -> 1993 has increased by 10.8 days.
We look at farms, where Jefferson had the inclination to measure things he measured it in the house
in those days. There is a farm in Wisconsin (Aldo Leopold wrote a book called; A Sand County
Almanac) where he lived and there they found that events are occurring about 7 days earlier. That is
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