Fredi: In June this year I was at a conference on extreme weather in the city of Toulouse
in France and it was a conference where basically all the researchers who work on
extreme weather come together and meet.
And while we were there we were actually experiencing a really extreme weather event: there was
a very strong heatwave that was hitting.
And it was so hot, some of the researchers were so badly affected that they could not
attend some of the sessions at the end of the week.
And while we were there a lot of people from
the media and colleagues, were asking us what’s the role of climate change in this heatwave
and we decided to take this opportunity that we were all together in the same place and
we would actually do an attribution study in real time while we were experiencing the
heatwave ourselves.
And so we did the study and found that this
heatwave would have been four degrees cooler if it had happened at the beginning of the
twentieth century.
Hi, I’m Adam and that was Dr Friederike Otto, aka Fredi.
She’s the Acting Director of the Environmental Change Institute and an Associate Professor
in the Global Climate Science Programme at Oxford.
And she’s an expert on extreme weather and climate change.
When we talk about climate change, what do we actually talk about?
Well, often, we discuss the future - say what the climate might look like in the year 2100.
We also talk a lot about averages - for example, limiting the global average temperature rise
to 1.5 degrees Celsius, 2.7 degrees Fahrenheit.
But this isn’t how we experience things like rain, temperature, wind.
We experience them here, and now.
In the form of weather.
Now weather and climate are different things, but changing the climate means changing weather
patterns.
Fredi: By looking at the effect of climate change on weather and particularly extreme
weather, we also make climate change real, even for ourselves.
Because usually when thinking about climate change we think about mean temperatures; we
think about the future.
But the weather is actually changing now and it’s changing in our backyard, no matter
where that backyard is.
But can researchers really link what’s happening in our backyards, to our changing climate?
Sure, we’re having extreme weather now, but disasters like floods and heatwaves were
around before humans started pumping greenhouse gases into the atmosphere.
So surely we can’t say climate change is causing them.
Fredi: Climate change is never the only cause of an extreme event, but it can make an extreme
event more likely or less likely or more intense.
And so the way that we can answer the question ‘did climate change cause this event?’
is by asking this slightly more complicated question of whether and to what extent did
climate change alter the likelihood of the event to occur?
Researchers like Fredi look at extreme weather events to try and answer this question: how
did climate change affect the chances of a particular event happening?
To do this, they investigate how likely that disaster is to take place in today’s climate.
And then they do the same calculations, but for a hypothetical world which is exactly
like ours except for one crucial difference.
Its atmosphere is free from the emissions from burning fossil fuels.
Comparing these two worlds allows researchers to work out climate change’s role in specific
events, rather than just making general statements like ‘on average heat waves are becoming
more common’.
Research like this can reveal, for example, that Tropical Storm Imelda, which brought
torrential rain to Texas in September - was made twice as likely by climate change.
But there’s a challenge with this kind of work.
Fredi: Usually when we do a scientific study it takes about a year from finishing the study
until it actually is published and people can read about it.
But when an extreme weather event happens people usually immediately ask the question:
is this climate change or not?
So Fredi and others have pushed to answer this question, while people are still asking
it - while the weather event is still fresh in our minds.
Not years or months after extreme weather hits, but in the immediate aftermath.
Even sometimes as the disaster is still unfolding.
And this is a huge challenge: to look at something that plays out over years, decades, and centuries—climate
change—and try to answer questions about yesterday.
It requires a research race against the clock.
Fredi: We just stop everything else, and for a week or so we do the study so that while
people are asking the question we are able to provide some scientific evidence.
While their methods are peer reviewed and published, the team don’t go through the
laborious peer review process for each individual study before presenting the results.
This means they can publish the results of these ‘rapid attribution’ studies as quickly
as possible.
But that also makes presenting the findings pretty daunting.
Fredi: I think every time we do a rapid attribution study and we go out to the press briefing,
and the next day afterwards, I’m very tense and waiting for some other scientist to have
found a massive mistake, but thankfully that hasn’t happened yet.
So what have rapid attribution studies like these shown?
Today, human activities have already heated the world by about one degree Celsius - 1.8
degrees Fahrenheit.
That might not sound like much, but extreme weather research is showing that this can
have a massive impact.
Fredi: When we first did a study on a European heatwave and found that actually our best
guess is it has been made one hundred times more likely, so climate change is a complete
game changer, that was a surprise.
Startling results like these help bring home the scale of what we’re doing to our climate.
And years after the first rapid attribution study, the work still regularly makes headlines.
Fredi: People do care about the answers we can provide, even much more so than I actually
expected.
Even if there have been 30 studies on different heatwaves that have been happening in different
parts of Europe and the numbers aren’t that different, people still really want to know
what does climate change mean for this heatwave that i’m just feeling now in the city I
live.
But the work isn’t just about painting a clearer picture of climate change’s local,
human impacts.
The results show that - even today - weather that used to be rare - extreme - is becoming
more common.
And our infrastructure just isn’t ready for that.
Fredi: We have to change how we deal with summer.
So the houses we live in are not built for temperatures above 30 degrees.
So we really have to adapt.
Even rich educated Europeans who are really not the ones who suffer most from climate
change, even we really have to change our own behaviour to adapt to climate change.
[[Some countries are already taking these changes on board, drawing up plans so that
they can spring into action when disaster strikes.]]
Fredi: I got contacted by people from the German parliament who said they have now brought
in a heat action plan in the German parliament, and they just wanted to make me aware of it,
that they were really made aware of the importance and the huge changes we see in the intensity
of heatwaves by our work.
So that was a very great and nice feedback to hear and see that actually our work has
impact on quite a large scale.
Fredi’s hoping that this work can have an even bigger impact, by getting weather forecasters
involved.
By giving national weather services the tools to work out the results for themselves, you
could look forward to regularly hearing about the role of climate change in your weather
forecast pretty soon.
Fredi: [[One thing that we are actually starting to work on now is not to do these kinds of
studies as a part of a research project where everything depends on who has time to drop
everything and do an attribution study, but to work with national weather services and
make this part of the national weather forecast.]]
And so what used to be really cutting edge five years ago we will get every time there
is an extreme weather event with the weather forecast on the event as well, which I think
is very exciting but also great because it also gives a lot more time for us scientists
to work on the cutting edge problems associated with this.
And what kinds of cutting edge problems are these?
Well perhaps the thorniest problem of all - how we turn climate research into action
that can combat and adapt to climate change.
Fredi: So now we can do attribution studies, we can say what is the role of climate change
in an individual event, so what?
So how can we use this science, or can we use this science for example in court?
Is it something that lawyers can use to help their climate litigation cases that we’re
seeing a lot of at the moment?
And also, what is the impact of these kinds of research on social movements that we see?
Can this science be used if we phrased it in a different way, if we asked the question
in a different way, to help the most vulnerable groups affected by climate change?
Ultimately, linking extreme weather with climate change is a way for us to link our emissions
to our experiences.
And maybe that will help us truly understand the consequences of our actions.
Fredi: With these attribution studies, especially when we do them quickly after the event has
happened or while the event is happening, we remind everyone all the time that climate
change is really happening here and now.
ANd even if other big things are happening on the political scene, that people will not
forget how important climate change is for their everyday life.
And if we do not stop emitting greenhouse gases, it will just make everyday life worse.