Lethal Heating: 07/28/19

28/07/2019

How Much Has Tasmania's Climate Changed In The 100 Years To Now?

ABC News - Erin Cooper

Scientists say sea levels in Tasmania are rising by 3mm a year. (Facebook: Discover Tasmania)

Key points:

Tasmania's average temperatures are now a degree warmer than a century ago
Rainfall has also decreased as climate change results in less low-pressure systems
Sea levels are rising by three millimetres a year

We have all heard how bad it is going to get: a million species at risk of extinction, entire island nations going under as sea levels rise and more severe weather events more often.
Scientists and international organisations have been issuing the climate change warnings for decades, saying the future of Earth as we know it is under threat.
Tasmania — renowned for its natural beauty — is not immune, suffering its fair share of natural disasters and slowly-eroding land, all attributed — at least in part — to the changing climate. But if we know a bit of how bad it is going to be, do we know how bad it already is?
The ABC investigated how much the island state's climate has changed in the past 100 years.

Usually wet rainforest wilderness areas have been scorched in the past few years. (Instagram: Fire Rescue Tasmania)

Feeling hot, hot, hot

Climate change 'unparalleled' on global scale

Scientists find global warming is being felt (almost) everywhere at the same time and the warming is unprecedented over the past 2,000 years.

Climatologist with the Bureau of Meteorology in Tasmania, Ian Barnes-Keoghan, said the bureau had been collecting temperature observations since the late 1800s — and the data paints a very clear picture.

"It doesn't matter how you cut it up, you still get the same message that temperatures over Tasmania have risen over the last century, particularly since the 1950s," he said.

"It's such a clear-cut story."
Averaged over the entire state, Mr Barnes-Keoghan said Tasmania is now about a degree warmer than it was a century ago.
But hot temperatures are also now more extreme than they used to be, with fewer very cold days.
"We're not saying that the temperature everyday is now a degree warmer than it was, but the average has moved up and we're seeing more of those extremely high temperatures, so your 35 and 40-degree days," Mr Barnes-Keoghan said.

Ian Barnes-Keoghan says a graph showing average temperatures shows the general increase of about a degree over the past 100 years, and especially since the 1950s. (Supplied: Bureau of Meteorology)

"Since 1910, there's been 12 days where somewhere in Tasmania has reported a temperature of 40 degrees or more. Four of those occurred in the first 93 years, the other eight only occurred in the last 17, and two of those were this year."

"It's often those extremes that people really notice."
As for the argument that the warming of the climate is cyclical, Mr Barnes-Keoghan said there was no reason why people should expect average temperatures will cool down again.
In fact, Scientists writing in the journal Nature this week said there was no evidence for "globally coherent warm and cold periods" over the past 2,000 years prior to industrialisation.
"We have a very good understanding of the mechanisms behind this warming, so the significant cause has been an increase in the concentration of greenhouse gasses in the atmosphere," Mr Barnes-Keoghan said.
"So just by simple physics that leads to an increase in the average temperature because more warmth is trapped close to the surface."

Tasmania is known for its freezing temperatures. (Supplied: Pat Fasnacht‎)

When it rains, it pours
Perhaps unsurprisingly, it is now also drier in Tasmania, with average rainfall across the state decreasing.

Ian Barnes-Keoghan says since the 1970s there have been fewer "wet" years, but 2016 was the second wettest on record. (Supplied: Bureau of Meteorology )

"There is less rain, on average, now than there was 40, 50 years ago, but there's a couple of things mixed in there," Mr Barnes-Keoghan said.
"One is that we still get wet years, like it rained a lot in 2016 — but the wet years have become less common and the dry years have become more common," he said.
He said the decline is strongest in late Autumn, heading into early winter.
Mr Barnes-Keoghan explained rainfall now behaves differently than it did in the past.
"[In the past,] you'd get a couple of dry years, then a couple of wet years to make up for it," he said.
"But sometime around the mid-70s, that pattern seems to have changed.

"Instead of having a mixture, it went to getting several dry years in a row, then a wettish year but not really that exciting, then a couple of dry years and just not getting those recharge years."

But explaining why is a bit more complex.
"Rainfall is complicated, but one of the reasons there's been less rainfall is there are less rain-bearing systems," Mr Barnes-Keoghan said.
"That partly comes about because of an increase in high-pressure systems — that's a known and expected consequence of increasing greenhouse gases.
"Rainfall is hugely variable from year to year, much more variable than temperature, so picking out trends in rainfall is much harder."
Mr Barnes-Keoghan also said the warmer atmosphere holds more moisture, so when it does rain, it's now often in quicker and heavier bursts.

But what about wind and snow?

No data is kept on snowfall but many believe it's not as prevalent as in the past. (Supplied: Cam Blake Photography)

So if Tasmania's drier, is it also getting less snow?
Mr Barnes-Keoghan said while it certainly seemed that way, there was no available data to back that up.

Ian Barnes-Keoghan says average temperatures are not expected to cool down again. (ABC Radio Hobart: Carol Rääbus)

"The bureau does not have a good long-term collection of snow data," he said.
That's because it doesn't snow that often over most of Tasmania and in particular, it doesn't snow that often in populated areas.
Mr Barnes-Keoghan said a lot of the historical observations really relied on somebody being there to take the measurement, which didn't always happen.
"I've been here for a long time and I get the impression that snow is less common than it was, but that's completely an anecdote," he said.
Wind is also hard to measure, though Mr Barnes-Keoghan said average windspeeds were decreasing, albeit not by much.
He said the bureau had only really collected data on wind since the 1990s, and even then, it might be skewed because equipment had been positioned in locations known to be particularly windy.
"To measure rainfall you basically need a jam jar, I mean we have very sophisticated jam jars which are calibrated, but measuring wind speed is really difficult," he said.

"The instruments we've got now were really only developed during the 1950s and only became widespread in Australia during the 80s and 90s. [They] only became really important around the 90s so we've really only got measurements since then."

Is Tasmania going under (the sea)?
Not quite yet, but sea levels are estimated to be rising 3 millimetres each year.
Retired oceanographer and sea-level-rise expert John Hunter said sea levels had risen by about 16 centimetres since 1841 — when the first sea-level benchmark was put in place at Port Arthur, on Tasmania's south-east coast, adding levels had risen by about the same amount "pretty much everywhere".

John Hunter kneels next to the 1841 sea level gauge which is carved into rock at Port Arthur. (Supplied: Frederique Olivier)

He explained that was due to two factors: the warming climate heating up water, causing it to expand "like liquid in a thermometer", and melting ice on land.
Mr Hunter said that while 3 millimetres a year might not sound like much, it had big consequences.

"The rule of thumb I use is that if you have about 10 centimetres of sea-level rise, which we've already seen last century, [the] frequency of flooding events goes up by a factor of three. So 10 centimetres trebles the amount of flooding events."

He said people tended not to notice the changes because they occurred over decades and coastal infrastructure was built accordingly, so "people just build sea walls a bit higher".
But people may see shorelines receding, which is one of the results of rising seas.
"For every metre of sea-level rise, you lose between 100 and 200 metres of shoreline," he said.

Wet years such as 2016, which saw heavy flooding, are becoming less common, according to the Bureau of Meteorology. (Copyright Neil Hargreaves)

NOTE: The ABC investigated changes in the island state's climate as part of our Curious Climate series. Curious Climate Tasmania is a public-powered science project, bridging the gap between experts and audiences with credible, relevant information about climate change. The project is a collaboration between ABC Hobart, UTAS Centre for Marine Socioecology, the Institute for Marine and Antarctic Studies (IMAS), the Tasmanian Institute of Agriculture (TIA), and the CSIRO.

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How To Talk Effectively About Climate Change

Scientific American - Max Boykoff

Our conversations have been stuck, but a new book lays out a number of ways to get them flowing productively

Credit: Getty Images

Lately, climate change has imposed itself on the public sphere. Through extreme events linked to changes in the climate, new scientific reports and studies, and rejuvenated youth movements (along with many other political, economic, scientific, ecological, meteorological and cultural events and issues) climate change has been increasingly difficult to ignore.
But you wouldn't really have picked up on that in the first round of the U.S. Democratic party primary debates that took place in Miami, Florida. As 20 candidates made their case to the American people, it was striking how minimally and shallowly they discussed climate change.
Sadly, this illustrates a contradiction we have been living with for some time. That is this: amid extensive research into the causes and consequences of climate change, climate communications—and thus, conversations about climate change in our lives—have remained stuck.
There are many reasons. Among them:

Climate change is still regularly treated as a single issue. This was clearly on display in the debates, and even during the paltry time devoted to surface-level discussions of climate change.
There has continued to be inadequate funding provided to support sustained and coordinated social science and humanities research into what constitutes more effective climate communications.
We have all been short on creativity, and we generally have stuck to ineffective climate communications approaches (e.g. merely scientific ways of knowing) as we muddle along.

Yet climate change is a collective action problem that intersects with just about every other area of life. It traverses critical issues such as public health, jobs, education, inequality, poverty, violence, trade, infrastructure, energy, foreign policy and geopolitics. While everyday people clearly have the capacity to care, they reasonably often focus on immediate concerns, such as issues of job security, local school quality, crime and the economy. In recent years, however, it has become more and more clear that these issues are interlinked with climate change.
So, in making these connections, we can more effectively get to the heart of how we live, work, play, find happiness and relax in modern life, shaping our everyday lives, lifestyles, relationships and livelihoods.
There has been an urgent need to improve communications about climate change at the intersections of science, policy and society. With that in mind, I wrote Creative (Climate) Communications. It is essentially a handbook that bridges sectors and audiences to meet people where they are on this critical 21st-century challenge. In the book I integrate research from the social sciences and humanities that has provided insights into better understanding what communications work, where, when, why and under what conditions.
I also examine how to harness creativity for more effective engagement. I integrate these lessons by assembling what I call features on a "road map" along with "rules of the road." The guide is then meant to help as researchers and practitioners proceed with both ambition and caution into struggles to effectively address the many issues associated with climate change.
Through this guidance, I seek to help maximize effectiveness and opportunities and minimize mistakes and dead ends in a resource-, energy- and time-constrained environment. In putting this together, I also emphasize that successful and creative climate communications strategies must be tailored to perceived and intended audiences and can be most effective when pursued through relations of trust. And I underscore that context is critical; cultural, political, social, environmental, economic, ideological and psychological conditions matter.
From synthesizing this work, I distill these lessons into some important "rules of the road."

Be authentic.
Be aware.
Be accurate.
Be imaginative.
Be bold.

From there, additional features on the road map help to navigate toward resonant and effective communications.

Find common ground on climate change.
Emphasize how climate change affects us here and now, in our everyday lives.
Focus on benefits of climate change engagement.
Creatively empower people to take meaningful and purposeful action.
"Smarten up" communications about climate change to match the demands of a 21st-century communications environment.

These rules and features can then help to meet people where they are in their everyday realities while opening up spaces for productive discussions and deliberations about climate change.
This approach can help to expand a spectrum of possibility for meaningful, substantive and sustained responses to contemporary climate challenges. Also, these "rules of the road" and the "road map" help make connections between climate change and other pressing issues that everyday people care about.
I also argue that an expanded approach involves processes of listening and adapting rather than winning and argument or talking people into something. Authentically considering other points of view fosters meaningful exchanges and enhances possibilities for finding common ground. Facts established through scientific ways of knowing about climate change are important, but they are not enough. We therefore need to enlarge considerations of how knowledge influences actions, through experiential, emotional, visceral, tactile, tangible, affective and aesthetic ways of learning and knowing about climate change.
Careful approaches informed by social sciences and humanities scholarship provide space and perspective for more authentic participatory engagement. They can overcome limited approaches and narrow mindsets that have blocked off these needed pathways. As a result, these approaches can then more effectively recapture what may be seen to be a "missing middle ground" on climate change in the public arena.
Through this systematic work, I hope we can better understand that a creative "silver buckshot" approach—in which different strategies are needed to reach different audiences in different contexts—will significantly improve creative climate communication efforts going forward. I hope my book catalyzes the ability of researchers, practitioners, decision-makers and everyday people to get more organized and steer our discussions and actions more productively.
As the Democratic primary debates illustrate all too well, we continue to miss opportunities to make deeper and more creative connections with climate change and related issues.

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Want To Do Something About Global Warming? Talk About It With Your Family And Friends

Los Angeles Times - Julia Rosen

Simply increasing the frequency of climate-related discussions shifted people’s perceptions of the scientific consensus around human-caused global warming, as well as their own attitudes on the matter, new research suggests. (Dreamstime)

There’s the old saying that you should never discuss politics or religion in polite company. Nowadays, it seems climate change has joined that list.
Barely more than a third of Americans broach the subject often or even occasionally, according to a recent survey by researchers at the Yale Program on Climate Change Communication.
All this not talking about climate change has given Americans a rather skewed perception of what the rest of the country thinks about the issue.
The average person estimates that only 54% of her fellow Americans believe climate change is happening. In reality, 69% do, according to the same Yale survey.
The more we talk about global warming, the more we might move the needle on public opinion, the Yale team reported Monday in the Proceedings of the National Academy of Sciences.
The researchers found that simply increasing the frequency of climate-related discussions shifted people’s perceptions of the scientific consensus around human-caused warming as well as their own attitudes on the matter.
“These findings suggest that climate conversations with friends and family enter people into a proclimate social feedback loop,” the researchers wrote.
Matthew Goldberg is a social psychologist at Yale University and lead author of the new study. He spoke with The Times about climate silence and how to break it.

What is climate silence?
Our most recent nationally representative survey shows that 69% of people find climate change to be at least somewhat important to them. But only 37% discuss it at least occasionally. So most people think it’s important yet most people don’t talk about it. This discrepancy is often referred to as climate silence.

Why don’t Americans talk about climate change more?
There are a lot of reasons. For some, the issue just isn’t salient to them. But there’s also a lot of research on perceptions about what others think. People are hesitant to talk about something that they see as contested or potentially controversial in their social network, so they remain silent.

But you found that people are often wrong when it comes to judging what others think about climate change. Does that help suppress conversation?
If you think everyone disagrees with you, or most people disagree with you, then you are not going to want to speak up. It starts this spiral of silence where people misjudge the beliefs of others, and then they remain quiet about this important issue.

Is everyone equally mistaken, or do misperceptions vary across groups?
In general, you tend to think that people around you share the beliefs that you have. So the most accurate folks were liberal Democrats. They were off by just 6 percentage points, guessing 63% instead of 69%. That’s likely because liberal Democrats know a lot of other Democrats, so they correctly believe that a lot of people around them believe climate change is happening.
Where we see the biggest discrepancy is at the opposite end of the political spectrum: conservative Republicans. If you’re only hearing from elite Republicans who are largely dismissive of climate science, then you are going to infer that a lot of people around you don’t believe it’s happening. So they were way off. They estimated the percentage was 48%.

Whether old or young, male or female, urban or rural, Americans tend to underestimate the extent to which other Americans think global warming is happening. (Yale Program on Climate Change Communication and George Mason University Center for Climate Change Communication)

It seems like this 69% must encompass a broader swath of society than just liberal Democrats. Who are the others?
There’s no doubt that it’s not just a liberal phenomenon, and I think that needs to be part of our messaging strategy.
We've been highlighting prominent Republican voices, to the best extent we can, to show that there are people across the spectrum that believe this is an important issue. It’s just that their voices aren’t loud enough.

Can you describe your new study?
We dug into data that we collected back in 2015, when Pope Francis was giving speeches across the United States talking about the importance of climate change, and there was a lot of change in public opinion because people heard about it more in the media.
In the surveys, which were taken seven months apart, people reported how frequently they talked about climate change with family and friends. We wanted to know whether talking more about it altered people’s perceptions of the scientific agreement around human-caused global warming, and we found that it did.

Why did you focus on the scientific consensus?
One reason is that past research coming out of our center has shown that it’s very influential. There’s still work to be done on why, but what I suspect it's because it's easy to communicate and it’s very powerful.

And what is the scientific consensus?
Studies show that 97% of climate scientists have concluded that human-caused global warming is happening.

When you looked at the numbers, what did you find?
We found that an increase in discussion — from rarely to occasionally, or occasionally to often — predicted a 2 to 3 percentage-point increase in the belief in the scientific consensus.
It’s a modest effect, but it matters a lot when you’re hovering around 50%, which is the most common estimate of scientific agreement. People have this false dichotomy that some scientists believe it’s happening and some scientists don’t.

What else happened when people talked more about this?
Changes in the perception of scientific consensus led to significant changes in people’s own beliefs that climate change is happening, that it’s human-caused, and in their worry about the issue. So those small changes can lead to big practical differences.

Why are family and friends so powerful?
Messengers matter very much. If a message comes from a credible communicator or one that has moral authority, then that will be very persuasive. And family and friends are the most important messengers. For one thing, they have closest proximity. They also are not easily ignored.

Your results suggest there's a kind of feedback loop. What's going on there?
We found that discussion leads to increased belief in the scientific consensus around human-caused warming and that belief in scientific consensus leads to more discussion. That could potentially start this positive cycle toward belief change.
It’s hard to say why that is. I speculate that once you have more certainty in a belief, it’s easier to go and share your belief rather than your ambivalence.

How do you suggest starting a conversation about climate change?
Start with common ground. To the extent that you can overlap the issue of climate change with the values of whoever you are talking to, the more effective your message will be.
For many people, climate change is really low on the list of issue priorities. But it’s so far-reaching that it can wrap into most other important issues. So you could take a healthcare angle, you could take a national security angle, an economic angle, or a campaign finance one. A lot of people care about these issues.
I find that taking a pollution perspective makes it very easy to talk to people about climate change. Because who is not against pollution?

What's another example?
We have a new study coming out where we engaged Christians on the issue of climate change. And we found that, of people that believe it’s happening, 19% cited protecting God’s creation as the single most important motivation for wanting to reduce global warming. That’s one in five.
We followed that study up with two experiments. We wrote messages that tried to convey that other Christians clearly care about this issue, and that it is our moral and religious obligation to deal with it. Basically, we said, "If you believe that God created this Earth, then this is something that you should want to protect and not allow to be degraded." And we found that that was a very influential message.

Isn't that kind of manipulative?
I see it more as understanding what’s most important to people. I’m trying to speak to what you care about.

Got any ice-breakers?
It’s almost comical how often weather is used for small talk. But that’s a good entry point. For instance, you could mention that there are temperature records being broken all over the world. Weather is also a good way to not touch on the buzzwords for potentially skeptical audiences.
Another approach is to weave in climate change if you’re already talking about another issue, like extreme weather or natural disasters. There’s a way to ease into it by saying something like, "Did you know that a warming climate will make hurricanes worse?"

In the big picture, how important is it that we start talking more about climate change?
I think it’s massively important, particularly because we are not doing it enough. A lot of the time, we assume that we are always going to be having these conversations with a skeptical audience. But in many cases, the other person cares about it just as much as you do.
There is the potential for it to backfire when you have people that are very strongly on the other end of this, but they are in the minority. This is why I emphasize the role of friends and family, because they are not relationships you can easily ignore.

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