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Climate Change and Sustainability
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How to Change the World
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From the lesson
Climate Change and Sustainability
Discussion about political and economic ramifications of climate change, including how to think big about sustainability
Meet the Instructors
Michael S. Roth
[MUSIC]
This week, we're going to be dealing with climate change and sustainability.
A great global challenge that many of those who sign up
for this class already known quite a bit about, others perhaps less.
So you'll have to bare with me as, if you've come to this week with a
lot expertise you may find some of these
things rather basic, but we have a class of
tens of thousands students and so we have to make
sure that we're getting some of the basic facts out.
Trying to understand also, why we should care
about these facts and then in the end once
again a big challenge what we could do in
the, in the face of, of global climate change.
So let's start of with some, some of the the, the basic facts
climate science has made enormous strides in, in recent decades we
understand patterns in the climate much better than we do, even 25, 30 years ago.
And now there is an enormous body of evidence, an enormous body of evidence
that shows that the planet is getting
warmer, and that human activity has contributed significantly
to the warming of the planet.
This, of course, was controversial for a while and
I guess part of the reasons it's controversial is
because the science is complex, it's based on big
data and computer modeling that is not easy to grasp.
It's not intuitive.
I think is also controversial because, it calls
to us, to change our behavior in ways,
that will have very serious economic consequences for lots of people, in the
industrial, and in the developing world different
kinds of consequences for those two regions.
But I, it, it's very clear now that the, that the massive consensis among
scientists around the world, is that the planet is getting warmer and that human
activities since industrialization in particular have contributed,
are contributing greatly to the warming of the planet.
The National Academy of Sciences in the United States, and
science, science, climatologists all over the world agree on this.
The human factor in climate change is really beyond scientific dispute
and it comes through mostly the burning of Greenhouse, or
the release of Greenhouse gasses due to the burning of fossil fuels.
You know, very, very clear I, I stress this because, in my
country, the United States, there are still politicians who want to deny this.
There are still industrialists who want to deny this, that it's the
burning of fossil fuels that is a great contributor to climate change.
And we, the scientists no
longer doubt about, have a, have doubts about this and, and you can, if
you try to find somebody who says, I don't believe it, yeah, that's great.
But there are thousands of scientists now who, who understand the
dynamic and who have prudently come to conclusions about how much
warming we can expect and what that warming will do to climate patterns and
to our way of life, in different parts of the world.
Now, the the projections for warming are may not
sound as frightening as you think. We, we believe that between
1.4 and 6.4 degrees celsius is the range of
the increase over the the, the coming
century, between 1.4 degrees Celsius and 6.4 degrees Celsius.
That's a very large range, right?
I mean, that's not, that, that's a significant range, and it's on top of an
increase since last century of .8%, .8% Celsius.
We have a, a, an animated map that allows you to see, the the,
the, the results of the, these changes. And, and, and I, I hope that putting it
in graphic form, makes it makes it even more clear.
what, where these trends are taking place, and over what periods of time.
In Elizabeth Kolbert's book, Field Notes from a Catastrophe, as she quotes
a climate researcher saying this is not something that is dramatic now,
that's why people don't really react, but if you can convey the message, he writes.
This is the climate scientists.
That it would be dramatic for our children and our grand children.
The risk is too big not to care.
I, I, I think that's the message really, we have,
the risk, the risks are too big not to care.
He went onto say right now its already five minutes past midnight.
In other words,
we have gotten so close to the edge of catastrophe we are in a
catastrophe that's unrolling, and yet the actions that
governments and industry are taking seem inadequate given the scale of the problem.
Now, why is that, I mean that's, that's the puzzling part of
this, right, is that we hear about the massive scale of the problem.
And yet we hear about these long negotations
that end in tepid resolutions about changing our behavior.
We continue to dump tons and tons of carbon into
the atmosphere, at increasing rates in many parts of the world.
That we have the science to develop a renewable
energy although we don't have it at the scale or
at the, with the economic framework that's necessary for massive use.
But, still, the reaction seems muted compared to the scale of the problem,
and one of the reasons that people have speculated that that's the case is
that we humans have a real hard time thinking long-term.
You know, we, we like gratification.
We like to get something done and then it's done and we
feel good about it.
You know, they, and many of you will know this
experiment about a delayed gratification where the the toddler is looking
at a marshmallow and is told if he doesn't eat
that marshmallow for five minutes he's going to get more stuff right.
And a lot of kids just as soon
as the experimenter's not there eat that marshmallow.
And in, the ones, some of them can wait, some of
them do things, the way they go like this, they don't
look at the marshmallow.
They, they do all these things so that they, they
can think of the long term, project into the future.
And scientists have studied these kids many years, over many years.
And they find the ones who could really wait are the ones who
do better on their tests, who seem to have more success in their lives.
And so the speculation is that it's, we have, if you can think in the
long term, if you can delay gratification lots of good things
will come in the wake of that willingness to delay gratification.
But the temptation to grab the gratification
right away is strong, you want to
employ more people tomorrow, so you want
a quick industrilization, we want cheaper gas.
We want we want to be able to cool our, houses in the summer more efficiently.
All these things, [SOUND] we can do right now.
We can do right now.
The long term consequence of doing
those things right now, scientists understand but
the rest of us seem to be, just focused on the near term.
And the neuroscientists, they, to, to say that, that's
because our brains were built for shorter term responsiveness.
And it's much harder to think about the world that our grandchildren will inherit,
than it is to think about, wanting to set your thermostat higher in
the winter and lower in the summer because that feels good right away.
If we continue to aim at feeling good right
away scientists have shown us we will destroy the planet.
We will destroy the conditions for life as we know it.
That's very dire and yet there are ways in which right now we
can change the trajectory of our impact on climate change.
There are, six major things that I want to talk about
that we know will happen as a result of climate change.
Rising sea levels, increase in rainfall and and in intense rainfalls in many parts
of the, the world, a decrease in snow and ice cover, increase in heat waves.
A change in the growing
seasons different parts of the world will experience this differently.
And then acid, acidification of oceans, the growing acid levels in the ocean.
There are lots of other things one could talk about,
but, I want to talk mostly about these, six areas.
Now, I, I should say that, many things it's,
it's complicated to make predictions in these areas because we're,
this is a very dynamic system with many, many variables.
And changing some of those variables will change all of the outputs.
Despite that complexity it is clear that the earths future climate,
the earth's future climate will be unlike the climate and that, that we have had
for centuries, and that over the last
10,000 years Humans, and other species, and other ecosystems
have gotten used to a certain climate. And we have, we thrive in a
certain climate. And that will change very, that is
changing very dramatically. Even in the 19th century,
some economists and scientists recognized that industrialization
was contributing to climate change. That dumping carbon
into the atmosphere had to have some impact on
the pattern, weather patterns because
carbon interacts with other elements in the atmosphere.
And that carbon can be reabsorbed in in
the earth by vegetation for example but, as we
put more and more carbon into the atmosphere, even in
the 19th century, economists speculated and scientists speculated that
we put more into the atmosphere than it could absorb.
And that there would be consiquences for that.
So, we're here today to talk with two of my
colleagues at Wesleyan and we're going to be talking about climate change.
You've met them before they, these are colleagues
from the, College of the Environment at Wesleyan.
And climate change is obviously one of the largest
subjects of public concern, of scientific concern, and our students will be reading
some short basic papers on the, the, the changes
in the in the climate and responsibility of humans for those changes.
And I, I thought we start off by just asking each of you to say just a few words
about what are the, the most important facts that
you think people should know about a climate change today.
I mean what, as you think
about citizens as, as researchers in this field.
What, what do you think that everybody should know about the climate change?
>> So, climate change is a reality.
And I want you to know that out there that, that humans are largely
responsible for the acceleration in climate change
that's happening because of our daily lives, and
this is being accentuated primarily by people in relatively
rich countries, for example, in the United States, and now in China, and what not.
And the key thing that we should know is, that what we, we're coming to a threshold
soon and what we choose as a world to do and will really
determine the prosperity of people on the entire
planet in, within the next 50 to 100 years.
>> I, I work in Peru with schools as well as native communities,
and we are doing these communal gardens with schools.
And, this, we do this to teach ecological literacy.
>> Yes. >> Which
is very low, abysmally low. And to motivate
the teachers, the administrators my colleague from Harvard and I give
workshop and we tell them, you know, now we're at 400 parts per million.
>> Yeah.
>> If we, when we reach 600 parts per million something cataclysmic
is supposed to happen.
And if we continue at the rate we are going, and don't do anything, this
is going to happen, as you say, within a hundred year, less than a hundred years.
So it is absolutely our responsibility to teach the new generation.
>> Yes.
>> and, and of course this kind of agriculture sequesters three times
by not cutting the trees, by not burning them.
>> Mm-hm.
>> And by putting biochar in the soil which keeps sequestering CO2.
>> Yes.
>> So, you know, it is, we try to not scare them.
>> Right, yeah.
>> You know, keep that balance, not too scary, but really
and I feel it intensely, I feel that we need to.
And that is in fact why I do what I do.
>> Mm-hm. >> Because otherwise
I would be despairing. >> Yeah.
>> So, direct action, and I love what Barry said, you know?
And this agriculture is both for food sovereignty,
and health, but it's also for climate change.
>> Yes.
>> I mean the great expert on, on this soil, and
biochar, is at Cornell, Johannes Lehmann, and he has created the
International Biochar Initiative. >> Mm-hm.
>> And according to him, if all agriculture,
were this kind of agriculture with biochar, we would
solve, our climate change, issue in a few
years of course, the obstacles to that are staggering.
>> Mm-hm.
>> But from my tiny experiment, and
from the studies of soil scientists and other
scientists, this kind of soil is
much more productive. In fact, experiment that he did with one
of his graduate students, he said it's 800% more productive and it's permanent.
So you can grow more food without any
agrochemicals, without petroleum products and it's healthy, and
you are sequestering CO2. So, it's my passion.
I push it whenever I can and this is something
you know, and we are trying to do it here.
Even though got bad news from Barry recently
[LAUGH] about the little experiment with biochar they did.
>> Yeah and, and that doesn't prove anything.
>> We.
>> Tell us a little bit, because some of
the, some of us won't know enough about biochar
and, and.
>> Okay so this, this soil
was discovered fairly recently by archaeologists.
>> Mm-hm.
>> In the whole Amazon basin, the low Amazon, the high Amazon.
And it's been studied.
The one who studied the soil is Johannes Lehmann, a soil scientist.
He was in Manaus for years, now he's at Cornell, has his lab.
And what gives
it is called [FOREIGN] in Brazil which means black
earth of the Indians, and it's still fertile today.
It's sold as potting soil.
>> I see.
>> And it hasn't been touched for 500 years, because nine out
of ten Amer-Indians died after the
Spaniards arrived, so the forest took over.
But there were great cities, it was a very populous, complex civilization,
that just vanished.
But the soil hasn't vanished, and the local people
know how to use it and continue to use it.
So it's really extraordinary. And the oldest ones are 8,000 years old.
The black color is given by biochar, now biochar is a particular kind of charcoal,
which is carbonized without oxygen. >> Mm-hm.
>> And it produces this biochar,
the name is very recent. >> Mm-hm.
>> I think it was given in 04 or 05. >> Mm-hm.
And ideally, you use agricultural residue. That's what we do.
>> Yeah.
>> To make biochar, and it is porous so it, it can retain nutrients.
The nutrients stick to it. >> Yes.
>> And the torrential rains don't wash out.
>> Mm-hm.
>> And it sequester CO2. >> Mm-hm.
>> So I
am taking it on the word and the work of the scientists.
>> Yes.
>> I have not had, this, scientifically, legitimized
in what I do, we just know that on degraded land, we have bumper crops.
>> Nice, yeah.
>> Where nothing grew, so, but, you know,
I don't know about, is it sequestering CO2.
I just know that we need it.
>> It's
a good start, yeah.
>> We need it to not continue cutting the forest and burning it.
That sense.
So in those two things, we are, but whether additionally, they
sequester it I take it on the word of the scientists.
>> It, yeah the, the reason it's sequestering is because it, as you said,
it's, it's, the, the, the chemical term is pyrolizatoin.
>> Mm-hm.
>> Mm-hm. >> That is it's formed without
oxygen so actually none of the carbon leaves
into the atmosphere in the formation of this.
Now it doesn't suck carbon out of the
atmosphere but what happens is, is that when
the roots of the plants respire they actually,
just like we do, they give off carbon dioxide.
>> Mm-hm.
Right. >> And then it sticks to the, to those
clay, clay-like soil particles. >> Mm-mm.
What many people don't realize, which really contributes a lot to climate change
Is that when people till the earth and turn it over for replanting, huge
amounts of soil are, are released. So for example, in tropical areas.
>> Carbon, carbon. 800.
Yeah. 832 metric
tons per acre of carbon dioxide is released into the atmosphere in the
temperate zone or an average like the United States, it's about in excess of 6
metric tons per acre that's released into the atmosphere.
And that comes from both microbial respiration, and
plant root respiration, so this stuff is able to,
to stick it and unlike with normal, with normal
agriculture for biochar, you do not tilt the soil.
You just plant and then you're returning the excess back into the soil.
So the process of formation doesn't release Carbon into the atmosphere and
the carbon of root respiration doesn't go. So it, it has that, that property.
And one thing's that you know, Frederick has brought up
the issue of the relationship of climate change to global temperatures.
What I'd like to point out is that, if we don't put another molecule of carbon
dioxide into the atmosphere today, the Earth will
still heat for another 63 years on average.
Because the carbon dioxide
remains in the atmosphere for an average of about 63 years.
So, so even with what we have, the experts like Jim Hanson are, are
convinced that we are committed to about a degree and a half of global
Centigrade of global warming. And we should know that
every grain crop that exists whether it's wheat or maize,
barley, etc.,
for every degree Centigrade nighttime temperature that the Earth heats up,
there's an approximate diminution of productivity by about 10%.
That includes rice.
So as the Earth heats up, our, the current plants that we have will
be decreasing their productivity and this has been taking place for quite a while.
>> So the, the question of the effects on people in different parts of the world.
is, is one that I know policy makers
and citizens and corporations are, are much concerned with
and I, I'd like to talk a little bit
I guess about the differential effects of climate change.
I mean it is
a global phenomenon.
Everyone will be effected somehow but you know you
hear people joking about it, you know, weather's nice.
And they say oh, I like this climate change.
It's warmer in October.
And, and I guess there will be I hate to put it so crudely,
but winners and losers or people who will be more vulnerable and less vulnerable.
And after I, maybe we can, we can just talk about that.
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