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Welcome back -- -- microphone stuck in my Philly man that command is author of the hockey stick and the climate wars dispatches from the front lines.
And that is the director of the Penn State earth system science center and in 2007 shared a noble prize.
With a team of scientists from the Intergovernmental Panel on Climate Change and co-founder and -- contributor.
To the award winning science website real climate dot org -- -- going to be back in the show thank you.
-- -- -- -- -- -- -- -- What this extreme weather we're having this summer is this part of what climatologists are talking about when they talk about global warming.
Absolutely I mean we've you know decades ago.
That we would be seeing increased incidents.
He -- of the sort that we're seeing across the US rate now.
Summer drought to.
Rising sea level.
A lot of what were -- on our TV screens and indeed outer windows.
Are very much the sorts of things that we have been predicting for some time now.
-- we are seeing.
The impact of climate change.
In our weather.
Now and new -- and was meant it was almost a hundred degrees on.
Over the weekend it's been in the ninety's it's -- cooling down the last couple days but it's not as simple as saying hey it's really hot out.
Global warming is taking place it's not that simple right.
You know exactly what climate change and global warming and does essentially.
Is it loads the weather -- so you know we.
To some extent whether can be thought that the -- -- of the tight there's a random component but what we're doing is we're loading those -- And in fact we're loading those dice in the cents.
So that sexes are coming up ten times as often as they ought to we are seeing.
Warm temperature high temperature.
Records across the US broken at ten times the rate we would expect.
From chance alone.
So far this summer so we are seeing the loading of the weather.
So -- is are these changes and this extreme weather pattern we're saying is -- happening.
Two earlier than you expected is it happening at a faster rate than we anticipated or things right on schedule.
The hornets on schedule in fact it was a very interest -- steady a few years ago by some scientists from the National Center for Atmospheric Research.
In the foothills.
Of the Rockies in Boulder, Colorado and was actually -- it was closed down.
By the -- a wildfire that broke out to.
Couple weeks back so scientists -- the national center for atmospheric research in boulder.
I'm actually published a study.
Several years ago that.
The rate at which we are now breaking an all time record.
Records for extreme heat in the US both in the observations.
Indian model simulations that we're -- The increasing concentration of greenhouse gases -- do the human activity and the modeled more or less -- what we're seeing in the observations so when it comes to.
You know breaking an all time records for -- in the US.
We're more or less come on schedules the problem is that if you.
Project those models forward another couple decades -- what they tell you is what we're seeing right now will be typical.
Summer conditions it will be extreme.
-- -- don't have a whole other set of problems that will be associated with -- now how much of this is caused by our presence on the planet.
Well he -- they are.
Our that the fact that we are you breaking records that -- set in the dust bowl years so we're literally shattering.
Records for high temperature across the US.
We have just set.
A record now for the largest percentage of the continental US that has ever been in -- 60% of the country is now -- -- to pump.
So we are literally breaking all sorts of records for extreme weather there's actually an index that measures.
All sorts of extreme weather and that index is now at its highest value ever for the US.
And if there's a context for understanding this isn't just.
Individual weather events we know that the past six months.
-- the warmest first half of the year ever for the US the past twelve months.
Don't -- -- twelve month period on record for the US there's a context that we are seeing.
Climate change and global warming literally impact the weather that we are feeling here in the US.
As is typical just the ebb and flow of climate change it happens over centuries.
Or is this -- something different than that.
It's different and that we we have now increased to you know we know.
That we have increased concentrations of CO2.
In the atmosphere.
That we know we haven't seen for at least 800000 years and most likely we haven't seen for millions of years.
So we are engaged in an unprecedented experiment in terms of what we're doing to the composition of our atmosphere.
We know into the greenhouse effect is very basic sciences physics that we've known for nearly two centuries.
It's not you know.
-- you -- to I think it's controversial from the way it sometimes needed.
It's not controversial science we -- the greenhouse effect -- -- we know we've increased those greenhouse gas concentrations to unprecedented levels what would be.
Really a difficult to understand would be if the climate was not changing of the -- -- Warming without a doctor Michael Mann of the author of the hockey stick in a climate where.
But how much of this is main clause that seem to be a whole other area of controversy.
Right so you know you'll sometimes hear.
Climate scientists say.
That most of the warming of the past -- -- A hundred years of the past fifty years is due to human activity.
But if you look at -- a little bit more closely turns out.
But that's actually even a little bit not misleading.
Because if you look at the effect of natural factors alone -- volcanic eruptions which have a short term cooling effect but if you have a whole bunch of eruptions like we have in the latter part of the century.
You actually tend to cool the climate.
If you have -- -- deepening of the brightness of the sun that can cool the climate.
And a quick look at the effect of those natural factors the models tell us that the globe -- cool.
In recent decades -- natural factors alone were at work the globe should have cooled.
But the globe is warmed.
Markedly even stakes of what should've been a natural.
It was at the indicator that indeed we are our presence here in our behavior.
Has an effect Thomas.
There's that literally no question within the scientific community that that's the case.
Now what do we do about it if indeed it something we are doing is helping contribute to it.
What do we do to change.
That it's a great question and you know the first thing we have to do is recognize.
I'm that there is a good state debate.
That can be had a for what to do about the problem and there -- you know there's room four.
Various sort -- how we go about dealing with the problem but there isn't room before.
Debating whether or not the problem exists -- the step and hopefully it's a step that we will achieve in the near future.
Is to move past this manufactured debate about whether the problem Israel on -- that -- the discussion to be had about how to go about solving the problem.
Right and well would be a first step.
Well you know ultimately we have to shift away from our reliance on fossil fuels -- you know we're not talking about cold Turkey -- And we're what we're talking about is incentivizing non carbon based sources of energy renewable energy like you know the rest of the world is doing China India.
-- a developing and we are following behind it's become a matter of economic competitiveness -- That you and is that because of the political debate in the money going toward those big.
The lack of believing in science.
Well you know unfortunately you know and I talk about this in my book you know -- -- keeping the climate wars there has been this war this effort to by vested interest to see themselves as losing out if we shift away from our addiction to fossil fuels.
Just like the tobacco industry tried to discredit the science linking their product to human health impacts that.
Fossil fuel industry and in various front groups that advocated for their interest have basically waged.
A disinformation campaign to try to cloud.
The science to try to fool the public to mislead the public to make them think.
That there is no problem.
Well I hope we can get beyond the political debate and get to some real science.
And when you know you hear the other side say well for every scientists like doctor -- we UV we can provide our own that say this -- -- Blige.
-- not equivalents at.
That there isn't you know and it's almost silly you know that you can say is sometimes these folks who put forward petitions write it will be.
Supposedly signed by all sorts of important individuals including scientists who will contest you know the scientific consensus that climate change is real.
And actually ABC news some years ago dug into one of the most popular of these so called petitions the -- petition.
And it turns out that the -- Turk signatories.
And people like get The Spice Girls and members of their.
The cast from the TV series mash I mean it was they were all sorts of non you know nonsensical.
You know names on the petitions petition and very few of them were actually scientists some of the weren't -- alive and so when he did he just a little bit that beneath the surface what you find.
If there's no credibility that -- look the US National Academy of Sciences has stated very clearly.
That climate change is real and it represents a threat.
-- national academies of all of the major industrial nations.
Have also stated.
For the record that climate change is real and it represents a threat.
Well the it's very important that people -- -- book to the hockey stick.
And the climate wars dispatches the front lines doctor Mann thank you very much once again for coming on the program tonight thank you -- -- -- what -- them.