Showing posts with label extreme weather. Show all posts
Showing posts with label extreme weather. Show all posts

Monday, July 16, 2012

It's raining metaphors

Now that the US is suffering unprecedented extreme weather events, including heatwaves, drought, wildfires, storms and floods, their mainstream media is paying attention to climate change.

It helps that NOAA just released an important new report that shows the connection between specific extreme weather events and climate change.

ClimateProgress reports that all mainstream media have reported the connection between extreme weather and climate change. 

Bill Blakemore on the American ABC News website gives journalists a lesson in how to talk about the link between climate change and extreme weather. He uses three metaphors that have the stamp of approval from real scientists.

Here's a quick overview.

The Parable of the Pot. He uses a pot of boiling water to illustrate that turning up the heat results in more bubbles in the water. Scientists won't say that any particular new bubble is caused by turning the heat up, but they will say that the probability of more bubbles is increased when you turn up the heat.

Baseball Player on Steroids. This short animation shows that when a baseball player takes steroids his run rate is higher (featured earlier on this blog here). You can't say that any individual run is due to the steroids, but the player gets higher run totals due to the steroids. They ban steroids to prevent this. In the same way, we need to reduce greenhouse gas emissions to prevent extreme weather events.

Loaded Dice. This analogy shows that climate change increases the odds of extreme weather events. It has been used consistently since 1988 when James Hansen took two painted dice to his presentation to Congress. We featured it earlier on Thisness of a That, here.

Blakemore offers a phrase that everyone can use to describe the link between climate change and extreme weather events without using the 'cause' word,
This exactly fits the pattern long predicted of increasingly frequent severe weather events.

In contrast, Dan Lashey from the National Resource Defence Council argues that we can come right out and say: Carbon pollution causes extreme weather. He notes that cigarette packs no longer say tobacco 'may cause harm', they say: Smoking causes lung cancer.

If newspapers can report that 40 people died because of a heatwave, I don't see why they can't report that an extreme weather event was caused by global warming (or climate change or carbon emissions). 

We can expect to see more variations on these statements as mainstream media tackles the task of connecting the dots between climate change and weather.

UPDATE: Paul Krugman uses the Loaded Dice analogy in this piece in the New York Times where he concludes: 
... large-scale damage from climate change is no longer a disaster waiting to happen. It’s happening now. 

Tuesday, May 1, 2012

Stacking the deck

In a stacked deck the cards are no longer in random order, instead they are arranged to favour specific outcomes.

Climate change stacks the deck for certain types of extreme weather events. As the planet warms scientists expect heat waves to become more frequent, longer lasting, and more intense. With them will come droughts and wildfires. As well as more 'hot and dry' events scientists predict there will be more extreme wet weather including storms and flooding.

This has tremendous implications for water resources and agriculture. When we break records now—and we are breaking thousands of them—we break them by a lot.

Reinsurers like MunichRE report that extreme weather/climate events have increased in recent decades. This graph shows events for 1980-2010. It's interesting to see that geophysical (earthquakes, tsunamis & volcanoes) events have not changed much, whereas the climate/weather related events have increased markedly over the 30 years.

[Click to enlarge]

Global warming has stacked the climate deck towards more exteme weather events that will destroy livelihoods and wealth in rich countries as well as poor countries.

Heidi Cullen, Chief Climatologist for Climate Central, used the 'stacked deck' metaphor in a Daily Beast article (22/4/2012).

Wednesday, April 25, 2012

A grand symphony weaves complex patterns

While Mark Twain said “Climate is what we expect; weather is what we get,” Heidi Cullen, chief climatologist for Climate Central, describes climate as an orchestra.
I think of climate as being like an orchestra. It has so many elements, the way an orchestra has many sounds. 

If you have listened deeply to complex orchestral compositions from different composers, you'll see that the analogy fits well. From mild, balmy climates to the freezing arctic or windy mountains, there's music to match.

Orchestral music can mimic the rhythms of climatic variation, the oscillating repetitions of El Nino or the Arctic Oscillation Index, as well as unexpected variations on a theme.

Cullen notes that climate change has added a new element to the music played by the climate orchestra— a steady drumbeat of warming in our climate system, caused by us.

What should you listen for when you listen to the climate orchestra? While you enjoy the seasonal riffs, the musical motifs and embellishments, the highs and lows, and the transitions, don't lose track of the rising tempo of the kettle drums up the back.

They are counting the increasing number of extreme weather events. Last year, 2011 set the record for the most billion-dollar weather disasters—14 of them, in one year.

Sunday, April 1, 2012

The clothes dryer effect

Just as a clothes dryer uses warm air to evaporate more easily, so our warming planet is drawing more moisture into the atmosphere. This moisure is leading to more extreme weather.

A report released in March 2012 by the Intergovernmental Panel on Climate Change confirmed that a strong body of evidence links global warming to an increase in heat waves, a rise in episodes of heavy rainfall and other precipitation, and more frequent coastal flooding. 

We're lurching from one weather extreme to another. The United States saw a February freeze followed by record breaking warm Spring weather where farmers are planting six weeks early.  Across Europe, people died by the hundreds during a severe cold wave in the first half of February, but a week later revelers in Paris were strolling down the Champs-Élysées in their shirt-sleeves. Australia has gone from a 10 year drought to record breaking floods.

Scientists say that the loss of Arctic ice is part of the story.
The question really is not whether the loss of the sea ice can be affecting the atmospheric circulation on a large scale, the question is, how can it not be, and what are the mechanisms?
Jennifer A. Francis, a Rutgers University climate researcher

Thomas C. Peterson, a researcher with the National Oceanic and Atmospheric Administration, used the clothes dryer analogy in this NYT article.

Thursday, March 29, 2012

Boxing kangaroo

Here's the professor training his boxing kangaroo called Weather.

The way I like to think about it is to think of weather as a boxer throwing punches at us. Over history, weather has always thrown these punches at us – in Brisbane we had floods in 1974, and in the late 1800s we had floods that went through Brisbane as well. So there’s always been these punches coming at us, but what we’re doing now with global warming is like training the boxer to throw harder and faster punches at us.
John Cook, Skeptical Science

You could say we're not just training Weather, we are also giving him a different feedmix – one with more carbon dioxide, methane, nitrous oxide, and ozone.

Loaded dice

How do we know whether today's weather event is caused by climate change? While we can't yet link specific events to climate change, scientists can look at patterns of extreme weather and ask whether the likelihood of these events was heightened by human-driven climate change.

Think of a pair of dice that you throw every day. Rolling a pair of sixes happens now and then. But rolling five in a row looks suspicious.  Human-induced climate change has loaded the dice toward certain extreme events.

In their paper, Public Perception of Climate Change and the New Climate Dice, James Hansen, Makiko Sato, Reto Ruedy find that 
Hot extremes, which covered much less than 1% of Earth's surface in the period of climatology, now typically cover about 10% of the land area. It follows that we can state, with a high degree of confidence, that extreme anomalies such as those in Texas and Oklahoma in 2011 and Moscow in 2010 were a consequence of global warming, because their likelihood in the absence of global warming was exceedingly small.
Proceedings of the National Academy of Sciences, April 2012

The loaded dice analogy was used by Dim Coumou, a climate scientist at the Potsdam Institute for Climate Impact Research in Germany in this Washington Post article on 29 March 2012.

Climate Bites has a good post on dice. They note that climate change has put an extra six on the dice (e.g. the five  got an extra dot). When you roll the dice now you are twice as likely to throw a six, and you never know whether this particular six is the ordinary, by chance, six, or whether it is the new climate change six.

Joe Romm used the loaded dice analogy in this article about  the unprecedented March (2012) heat wave that was “unmatched in recorded history” for the U.S. (and Canada).  New heat records swamped cold records by the stunning ratio of 35.3 to 1.