17/03/2020

(AU) These Are The Places Across Australia People Will Soon Struggle To Live In Without Serious Challenges

NEWS.com.au - Stephanie Bedo | Shannon Molloy

Roads melting, power supply dropping off and days reaching 50C — this is the bleak future Australia faces. So, how will your home town change?

Last year was Australia's warmest on record - 1.5C above the 1961 to 1990 average. Source: Supplied


Crushingly uncomfortable conditions, a greater risk of illness, economic turmoil, the destruction of ecosystems, extreme weather and ferocious bushfires.
It sounds like the description of some fictional dystopian society, but this is the stark reality that could face many Australian communities in the not so distant future.
Climate change is here and the consequences, both now and ahead, present significant challenges to all aspects of life, says Sarah Perkins-Kirkpatrick, senior lecturer and ARC Future Fellow at the Climate Change Research Centre at University of NSW Sydney.
“The impacts of climate change are far reaching, from losing our precious Great Barrier Reef to the loss of life because of intense heat and bushfires,” Dr Perkins-Kirkpatrick said.
“Our way of life will be affected, as well as our economy and unique environment.”
To illustrate the impact, these are some of the regions that will become difficult places to live.

Western Sydney
The western Sydney region has grown rapidly over recent years and is projected to be home to an extra 1.5 million people by 2056.
At the same time, average temperatures and the number of heatwaves are rising, and the types of new suburbs popping up aren’t designed to withstand harsher future conditions.
“We’re creating an urban nightmare in the west,” says Dale Dominey-Howes, a professor of science at the University of Sydney and an expert in hazards, disasters and risk.
Hotter days – and for longer – aren’t just uncomfortable. The impact of heat and heatwaves can be serious and western Sydney is vulnerable to a number of natural hazards.
Western Sydney is set to warm by 1.5C to 3C by the end of 2050. Already, the number of days over 35C has almost doubled in 25 years – and that number is predicted to jump.

This graph tracks the number of days over 35C for three major Sydney regions. Picture: Greater Sydney Commission, 2019



A heatwave in Australia during summer. Picture: Supplied

“It’s likely we’ll see days where the temperature reaches 50C in western Sydney by 2050,” Dr Perkins-Kirkpatrick said.
At that temperature, heatwaves can do things like melt roads and pathways, interrupt baseload power supply and make it less efficient.
And then there’s physical stressors on humans and animals, Dr Dominey-Howes said.
“For humans, you start by getting overly hot, sweaty and uncomfortable. As the temperature rises starts to affect your concentration and decision-making. You might do things that are more dangerous,” he said.
“At the threshold of 41C, critical internal organs – the heart, liver, kidneys and so on – start to function more poorly. Once past that critical threshold, they can actually start to fail and death is more likely to occur.”
LISMORE
  • Climate could be more like Mackay currently, average annual temp of 27.2C, summer of 30.5C, winter of 22.8C
  • At the moment, has a average annual temp of 25.4C, average summer of 29.2C, average winter of 20.8C
  • Average number of days above 35C goes from 3.6 currently to 10.5
COFFS HARBOUR
  • Climate could be more like Atherton currently, average annual temp of 26C, summer of 28.8C, winter of 22.3C
  • At the moment, has a average annual temp of 23.1C, average summer of 26.8C, average winter of 18.9C
  • Average number of days above 35C goes from 1.3 currently to 3.6
PORT MACQUARIE
  • Climate could be more like Noosa currently, average annual temp of 25.8C, summer of 29.1C, winter of 21.8C
  • At the moment, has a average annual temp of 23.3C, average summer of 26.8C, average winter of 19.3C
  • Average number of days above 35C goes from 0.6 currently to 1.7
NEWCASTLE
  • Climate could be more like Caboolture currently, average annual temp of 25.7C, average summer of 29.2, average winter of 21.3C
  • At the moment, has a average annual temp of 22.9C, average summer of 27.0C, average winter of 18.1C
  • Average number of days above 35C goes from 3.4 currently to 8.2
SYDNEY
  • Climate could be more like Grafton currently, average annual temp of 25.5C, average summer of 29.4C, average winter of 20.9C
  • At the moment, has a average annual temp of 22.7C, average summer of 26.7C, average winter of 18.1C
  • Average number of days above 35C goes from 4.9 currently to 10.9
WOLLONGONG
  • Climate could be more like Yamba currently, average annual temp of 23.7C, average summer of 26.9C, average winter of 19.9C
  • At the moment, has a average annual temp of 22.0C, average summer of 25.7C, average winter of 17.8C
  • Average number of days above 35C goes from 2.3 currently to 5.9
WAGGA WAGGA
  • Climate could be more like Dubbo currently, average annual temp of 24.3C, summer of 32.2C, winter of 16.1C
  • At the moment, has a average annual temp of 22.4C, average summer of 30.9C, average winter of 14C
  • Average number of days above 35C goes from 26.2 currently to 47.3
CANBERRA
  • Climate could be more like Mudgee currently, average annual temp of 22.8C, average summer of 30C, average winter of 15.3C
  • At the moment, has a average annual temp of 19.9C, average summer of 27.4C, average winter of 12.4C
  • Average number of days above 35C goes from 7 currently to 16.9
BATEMANS BAY
  • Climate could be more like Maitland currently, average annual temp of 23.7C, summer of 28.7C, winter of 18.2C
  • At the moment, has a average annual temp of 21.1C, average summer of 24.7C, average winter of 17.1C
  • Average number of days above 35C goes from 1.8 currently to 3.1
BEGA
  • Climate could be more like Toowoomba currently, average annual temp of 23.6C, summer of 28.3C, winter of 17.8C
  • At the moment, has a average annual temp of 21.6C, average summer of 25.9C, average winter of 17C
  • Average number of days above 35C goes from 1.1 currently to 2.9
Going about your daily activities, both at home and work, would become increasingly difficult and this would have a ripple effect across the economy.
“In addition, we know that hospital admission rates already rise dramatically during heatwave events because heat exacerbates underlying health condition,” he said.
“Sick, young and older patients are particularly vulnerable. But as we move forward, that demographic could expand to include groups currently otherwise considered healthy – individuals from 15 to 55. So, heat and heatwaves increase the burden on the health system.”

A huge number of people are moving to Sydney’s western regions, where temperatures are forecast to soar in coming decades. Picture: AAP


Heatwaves can increase the amount of atmospheric pollutants, making it harder to breathe and increasing risk of harm to lung and heart systems.
“We’ll have to change the Australian attitude to heat,” Dr Perkins-Kirkpatrick said.
“We can’t afford to discount the risks. Sucking it up, saying ‘she’ll be right’ and having a barbeque, won’t be possible down the road.
“We can’t be complacent about the impact of heatwaves in the future. This will be worse than what we’re used to, what we’ve experienced in the past.”
Heatwaves are silent killers now at it stands, but their death toll is likely to rise in the future.
“Now, more people die from heat on January 27 than any other day because millions of us are outside celebrating Australia Day (the day before), where exposure to heat and the presence of alcohol create a deadly combination,” Dr Perkins-Kirkpatrick said.

The steep rate of population growth in Sydney's western region. Picture: SAFi
But the risk is present throughout the year, with heat killing more Aussies than all other natural hazards combined annually.
The Black Saturday bushfires are considered Australia’s single greatest loss of life in a disaster, claiming 173 lives.
“But the heatwave preceding it killed at least 374 people in Melbourne alone. Some estimates are that it could be closer to 500 people,” Dr Dominey-Howes said.
Overall, the heatwave that rolled across the country and ultimately set the stage for Black Saturday, might have hospitalised up to 2000 people in Melbourne.
The consequences in a region like western Sydney is made worse when you examine the types of dwellings many people will occupy.
New housing estates filled with big dwellings constructed of cheap and dark materials on small blocks with minimal foliage, on streets with minimal tree cover, are suboptimal.
“Homes should have wide open spaces, decent distances between buildings for airflow, orientations that avoid absorbing heat, types and colours of materials that don’t attract heat and radiate it back out at night-time, and have a number of trees for shade and temperature control,” Dr Dominey-Howes said.
“Unfortunately, that’s all lacking in many of these western suburb planned estates.”
DARWIN
  • Climate could be more like Daly River currently, average annual temp of 33.9C, average summer of 33.7C, average winter of 31.9C
  • At the moment, has a average annual temp of 32.1C, average summer of 32C, average winter of 30.9C
  • Average number of days above 35C goes from 46.8 currently to 176.1
BROOME
  • Climate could be more like Elliott currently, average annual temp of 34.2C, summer of 37.4C, winter of 29.2C
  • At the moment, has a average annual temp of 32.4C, average summer of 33.5C, average winter of 29.6C
  • Average number of days above 35C goes from 80.9 currently to 166.7
PERTH
  • Climate could be more like Jurien Bay currently, average annual temp of 25.5C, average summer of 30.2C, average winter of 19.9C
  • At the moment, has a average annual temp of 24.1C, average summer of 29.9C, average winter of 18.4C
  • Average number of days above 35C goes from 16.8 currently to 30.5
KALGOORLIE
  • Climate could be more like Mount Magnet currently, average annual temp of 28.4C, summer of 36.8C, winter of 19.5C
  • At the moment, has a average annual temp of 25.5C, average summer of 32.8C, average winter of 17.8C
  • Average number of days above 35C goes from 41.8 currently to 67.8
ADELAIDE
  • Climate could be more like Pingelly currently, average annual temp of 23.3C, summer of 31C, winter of 15.8C
  • At the moment, has a average annual temp of 21.9C, average summer of 28.2C, average winter of 15.7C
  • Average number of days above 35C goes from 17 currently to 26.8
MOUNT GAMBIER
  • Climate could be more like Albury-Wodonga currently, average annual temp of 21.8C, summer of 30.2C, winter of 13.5C
  • At the moment, has a average annual temp of 19C, average summer of 24.2C, average winter of 14C
  • Average number of days above 35C goes from 6.4 currently to 10.4
South West Australia
The future situation in south west Australia paints a similarly stark picture.
This region will experience less rainfall, leading to drier conditions, ultimately affecting the economy through lower wheat yields.
In the future the rainfall change could be up to 25 per cent less than what it is now.
“Basically it’s going to significantly decline,” Dr Perkins-Kirkpatrick said.
“The weather patterns that bring rainfall to south west Australia are contracting towards the poles, or shifting south, particularly during winter, which is when the region receives the most amount of rain.
“A place that’s already reasonably dry is going to get drier, with implications for agricultural production, wine production and tourism.”

Rainfall reductions in the May to October growing period of southwest Western Australia. Source: WA Department of Primary Industries and Regional Development. Source: Supplied


In inland areas, frost days have increased by about two to four weeks, mostly because of clearer skies at night.
“That can have massive effects on what you plant and when you plant it,” Dr Perkins-Kirkpatrick said.
Agricultural water supplies have already decreased by up to 25 per cent.
Wheat yields have stagnated since 1990, in part due to changes in the climate, in an industry worth more than $5 billion a year.
“Rising temperatures and reduced rainfalls are responsible for the shortfall in wheat yields,” she said.
By the end of the century there could be up to 20 to 30 heatwaves days in a season, compared to five to 10 now.
“The number of heatwave days has increased significantly and they’re getting longer and hotter. The change isn’t as dramatic as other cities but it’s still there.”

CAIRNS
  • Climate could be more like Bamaga currently, average annual temp of 30.1C, average summer of 30.9C, average winter of 28.5C
  • At the moment, has a average annual temp of 29.1C, average summer of 31.6C, average winter of 25.7C
  • Average number of days above 35C goes from 3.9 currently to 17.7
CLONCURRY
  • Climate could be more like Elliott currently, average annual temp of 34.2, summer of 37.4C, winter of 29.2C
  • At the moment, has a average annual temp of 32.9C, average summer of 37.1C, average winter of 26.8C
  • Average number of days above 35C goes from 153.3 currently to 203.7
MACKAY
  • Climate could be more like Cooktown currently, average annual temp of 29.3C, summer of 31.8C, winter of 26.3C
  • At the moment, has a average annual temp of 27.2C, average summer of 30.5C, average winter of 22.8C
  • Average number of days above 35C goes from 1.5 currently to 8.3
LONGREACH
  • Climate could be more like Port Hedland currently, average annual temp of 33.3C, summer of 36.4C, winter of 28.1C
  • At the moment, has a average annual temp of 31.4C, average summer of 36.8C, average winter of 24.4C
  • Average number of days above 35C goes from 125.8 currently to 177.6
ROCKHAMPTON
  • Climate could be more like Charters Towers currently, average annual temp of 30.1C, summer of 33.7C, winter of 25.2C
  • At the moment, has a average annual temp of 28.1C, average summer of 31.7C, average winter of 23.5C
  • Average number of days above 35C goes from 13.6 currently to 38.6
BUNDABERG
  • Climate could be more like Mareeba currently, average annual temp of 28.7C, summer of 31.1C, winter of 25.3C
  • At the moment, has a average annual temp of 26.9C, average summer of 30.3C, average winter of 22.7C
  • Average number of days above 35C goes from 0.8 currently to 5.9
BRISBANE
  • Climate could be more like Mareeba currently, average annual temp of 28.7C, average summer of 31.1C, average winter of 25.3C
  • At the moment, has a average annual temp of 26.0C, average summer of 29.6C, average winter of 21.6C
  • Average number of days above 35C goes from 1.8 currently to 8.3
GOLD COAST
  • Climate could be more like Mackay currently, average annual temp of 27.2C, average summer of 30.5C, average winter of 22.8C
  • At the moment, has a average annual temp of 25.2C, average summer of 28.5C, average winter of 21.3C
  • Average number of days above 35C goes from 1.2 currently to 5.4
Far North Queensland
The Great Barrier Reef is one of the world’s greatest natural wonders and contributes much more to those living nearby – and all Australians – than a picturesque part of our geography.
The net social, economic and iconic value of the Reef has been estimated at $56 billion per year. The Reef directly supports 64,000 direct and indirect jobs and contributes $6.4 billion to Australia’s GDP.
It’s critical nationally, but especially to the Far North Queensland region where thousands of people rely on it for employment, and countless other businesses need it indirectly for their future prosperity.
But it’s in serious trouble because it’s threatened by multiple intersecting climate and weather-related processes, and the impacts of inappropriate land management.
“A temperature increase of 2C will completely change the reef as we know it,” Dr Perkins-Kirkpatrick said. “It’s very difficult to see how we don’t get to that point in the future.”

Underwater vision of bleaching on the Great Barrier Reef, off Port Douglas, taken on June 28, 2018. Source: Climate Council. Source: Supplied


Coral bleaching has occurred in the past on the Reef, but it’s happening with dramatically increased frequency and extent over recent decades due to warmer ocean temperatures.
The CSIRO Oceans report State of the Climate 2018 found there was a 0.16C temperature increase per decade since 1950.
That increase appears to be accelerating, which will contribute to more severe and more frequent coral bleaching events, Prof Dominey-Howes said.

The ocean surface around Australia has warmed over recent decades at a similar rate to the air temperature. Source: CSIRO Oceans report State of the Climate 2018. Source: Supplied


“The time to recover has gotten shorter and so the chances of a full recovery are impaired.”
It’s a stark reality already being seen, with a bleaching event in 2016 resulting in a staggering 93 per cent of the reef being damaged.
The Reef is also at threat from an increased acidification of the oceans, as well as the likelihood of increased tropical cyclone frequency and intensity.
“As the ecology of the reef changes, it can favour invasive pest species. Other plants and animals not traditionally there can come in and out-compete the natural ecosystem,” Prof Dominey-Howes said.
“Coupled with that, the washing off of sediments and other debris from the land due to poor land management practices.”



A temperature rise of 4C would destroy the Reef entirely – a scenario that’s not impossible if action on climate change is delayed or below current commitments.
“We’re struggling to keep temperature rises at 1.5C to 2C, so further increases will be extremely damaging to the reef, it’s health and diversity and productivity,” he said.
Once it’s gone, it’s gone forever and the loss will be more devastating than a pretty picture, with entire communities in the north potentially paying the price.

Southeast Australia
Over the past few months, Australian witnessed hell on earth as large chunks of the country – particularly in the southeast – were razed by ferocious bushfires.
There’s a very good chance we’ll see such destruction again in the near future, again and again, with greater intensity and frequency.
Once again, southeast Australia will be in the firing line.
“This is happening under 1C warming,” Dr Perkins-Kirkpatrick said. “Under 2C to 3C warming, we could see bushfire seasons that are even worse.”
Bushfires aren’t a new challenge in Australia and the most recent fires, which affected three-quarters of all Australians, would have occurred without climate change, Sarah said.
“But they wouldn’t have been as severe,” she said.

Bushfires in the area around the town of Nowra in New South Wales on December 31, 2019. Picture: AFP
From 1973 to 2010, the fire season in Australia’s southeast has lengthened and it’s projected to continue to do so into the future.
“It means there’s less chance for hazard reduction because the conditions to do those burns occur during a shorter window now,” Dr Perkins-Kirkpatrick said.
Intense fires, known as pyrocumulonimbus systems, interact with the atmosphere and create their own weather systems. They are more conducive in warmer environments, she said.
“The time between these ferocious fires has halved. Historically, we usually saw one or two a season. In the current season, we’ve seen 20 to 30.”
Australia’s southeast stretch is where most of the population lives, she pointed out, “and so the exposure of people and buildings is the highest”.

An image from the Himawari-8 satellite shows Australia’s southeast in the midst of the bushfires. Source: Supplied
“We will have to seriously shift our approach to a number of critical areas, from the design of homes and their locations to bushfire management plans,” Dr Perkins-Kirkpatrick said.
“We will also have to change what we farm and how we farm it, and that’ll have knock-on effects to the broader economy and cost of living.
“In addition to agriculture, bushfire seasons of the future will also impact a number of southeast Australia’s vital sectors, including tourism and viniculture.”
BENDIGO
  • Climate could be more like Wyalong currently, average annual temp of 23.3C, summer of 31.7C, winter of 14.8C
  • At the moment, has a average annual temp of 20.5C, average summer of 28.2C, average winter of 13CAverage number of days above 35C goes from 12.9 currently to 24.3
BALLARAT
  • Climate could be more like Bathurst currently, average annual temp of 20.2C, summer of 27.6C, winter of 12.7C
  • At the moment, has a average annual temp of 17.6C, average summer of 24.4C, average winter of 11C
  • Average number of days above 35C goes from 5.2 currently to 10.6
MELBOURNE
  • Climate could be more like Young currently, average annual temp of 21.7C, average summer of 30.3C, average winter of 13.2C
  • At the moment, has a average annual temp of 20.0C, average summer of 25.5C, average winter of 14.3C
  • Average number of days above 35C goes from 8.3 currently to 14.5
LAUNCESTON
  • Climate could be more like Bathurst, average annual temp of 20.2C, average summer of 27.6C, average winter of 12.7C
  • At the moment, has a average annual temp of 17.7C, average summer of 23.1C, average winter of 12.4C
  • Average number of days above 35C goes from 0.1 currently to 0.3
HOBART
  • Climate could be more like Cooma currently, average annual temp of 19.2C, average summer of 26C, average winter of 12.2C
  • At the moment, has a average annual temp of 17.2C, average summer of 21.7C, average winter of 12.5C
  • Average number of days above 35C goes from 0.6 currently to 1.4
Southeast Queensland
In 2019 the Queensland department of environment warned a sea level rise of 1.1m would cost $226 billion nationally by the end of the century.
Southeast Queensland is the hotspot for sea level rise risk, with an estimated 68,000 homes at risk of destruction.
Dr Dominey-Howes said there were several interacting factors that created this risk.
“In a warming world, each additional 1C rise means the atmosphere holds an additional seven per cent of water, which has got to go somewhere, so when storms happen, the forecasts are for increasingly intense rainfall events,” he said.
“If there are storms, then we have other processes that happen – we can have a storm surge and then you might get wave sets on top of that.
“So that means the extreme water level for future storms, under a climate change world, puts even more property at risk. The increasing risk threatens the sustainability of those communities.
“This has been a high growth corridor where a lot of people have been encouraged to settle, which increases the exposure above what would have otherwise been the case.”

Modelling of sea level rises on the Gold Coast. Dark blue is current day, light blue is the scenario in 2100. Picture: Coastal Risk Australia
Modelling of sea level rises on the Gold Coast. Dark blue is current day, light blue is the scenario in 2100. Picture: Coastal Risk Australia. Source: Supplied


The conditions that favour tropical cyclones are also more likely in southeast Queensland in the future.
“There is concern tropical cyclones could make their way further south,” Dr Dominey-Howes said.
With populations in the city rapidly growing, he said there would be more people and property at risk.
Tourism is now worth $4.65 billion annually to the Gold Coast’s gross regional product and employs 42,000 people, with 20 per cent growth year-on-year.
“Climate change has the real potential to curtail that growth in value.”

Is It Too Late?
Conversations about how Australia should respond to the challenges of climate change – or, as some continue to debate, whether we should at all – continue to rage.
But Dr Perkins-Kirkpatrick said it was critical for everyone to understand that it’s “never too little or too late to reduce our carbon emissions”.
“Everyone plays a part and no part is ever too small. We should never become complacent in our efforts to reduce our emissions now or in the future.”

Links

(AU) A Rare Natural Phenomenon Brings Severe Drought To Australia. Climate Change Is Making It More Common

The ConversationNicky Wright | Bethany Ellis | Nerilie Abram




  • Nicky Wright is a Research Fellow, Australian National University
  • Bethany Ellis is a PhD Candidate, Australian National University
  • Professor Nerilie Abram is an ARC Future Fellow and Chief Investigator for the ARC Centre of Excellence for Climate Extremes, Australian National University
Weather-wise, 2019 was a crazy way to end a decade. Fires spread through much of southeast Australia, fuelled by dry vegetation from the ongoing drought and fanned by hot, windy fire weather.
On the other side of the Indian Ocean, torrential rainfall and flooding devastated parts of eastern Africa. Communities there now face a locust plague and food shortages.
These intense events can partly be blamed on the extreme positive Indian Ocean Dipole, a climate phenomenon that unfolded in the second half of 2019.
The Indian Ocean Dipole refers to the difference in sea surface temperature on either side of the Indian Ocean, which alters rainfall patterns in Australia and other nations in the region. The dipole is a lesser-known relative of the Pacific Ocean’s El Niño.
Climate drivers, such as the Indian Ocean Dipole, are an entirely natural phenomenon, but climate change is modifying the behaviour of these climate modes.



In research published today in Nature, we reconstructed Indian Ocean Dipole variability over the last millennium. We found “extreme positive” Indian Ocean Dipole events like last year’s are historically very rare, but becoming more common due to human-caused climate change. This is big news for a planet already struggling to contain global warming.
So what does this new side-effect of climate change mean for the future?

The Indian Ocean brings drought and flooding rain
First, let’s explore what a “positive” and “negative” Indian Ocean Dipole means.
During a “positive” Indian Ocean Dipole event, waters in the eastern Indian Ocean become cooler than normal, while waters in the western Indian Ocean become warmer than normal.
Warmer water causes rising warm, moist air, bringing intense rainfall and flooding to east Africa. At the same time, atmospheric moisture is reduced over the cool waters of the eastern Indian Ocean. This turns off one of Australia’s important rainfall sources.
In fact, over the past century, positive Indian Ocean Dipoles have led to the worst droughts and bushfires in southeast Australia.
The Indian Ocean Dipole also has a negative phase, which is important to bring drought-breaking rain to Australia. But the positive phase is much stronger and has more intense climate impacts.
We’ve experienced extreme positive Indian Ocean Dipole events before. Reliable instrumental records of the phenomenon began in 1958, and since then a string of very strong positive Indian Ocean Dipoles have occurred in 1961, 1994, 1997 and now 2019.

The Dipole Mode Index is used to track variability of the Indian Ocean Dipole.
But this instrumental record is very short, and it’s tainted by the external influence of climate change.
This means it’s impossible to tell from instrumental records alone how extreme Indian Ocean Dipoles can be, and whether human-caused climate change is influencing the phenomenon.

Diving into the past with corals
To uncover just how the Indian Ocean Dipole has changed, we looked back through the last millennium using natural records: “cores” taken from nine coral skeletons (one modern, eight fossilised).
These coral samples were collected just off of Sumatra, Indonesia, so they’re perfectly located for us to reconstruct the distinct ocean cooling that characterises positive Indian Ocean Dipole events.
Scientists drilling into corals to study past climate. Corals are like trees, and grow a band for every year they live. Jason Turl
Corals grow a lot like trees. For every year they live they produce a growth band, and individual corals can live for more than 100 years. Measuring the oxygen in these growth bands gives us a detailed history of the water temperature the coral grew in, and the amount of rainfall over the reef.
In other words, the signature of extreme events like past positive Indian Ocean Dipoles is written in the coral skeleton.
Altogether, our coral-based reconstruction of the Indian Ocean Dipole spans 500 years between 1240 and 2019. There are gaps in the timeline, but we have the best picture so far of how exactly the Indian Ocean Dipole has varied in the past.

How unusual was the 2019 Indian Ocean Dipole event?
Extreme events like the 2019 Indian Ocean Dipole have historically been very rare.
We found only ten extreme positive Indian Ocean Dipole events in the entire record. Four occurred in the past 60 years, but only six occurred in the remaining 440 years before then. This adds more weight to evidence that positive Indian Ocean Dipole events have been occurring more often in recent decades, and becoming more intense.
But another finding from the reconstruction surprised – and worried – us. Events like 2019 aren’t the worst of what the Indian Ocean Dipole can throw at us.
Of the extreme events we found in our reconstruction, one of them, in 1675, was much stronger than anything we’ve seen in observations from the last 60 years.
The 1675 event was around 30–40% stronger than what we saw in 1997 (around the same magnitude as 2019). Historical accounts from Asia show this event was disastrous, and the severe drought it caused led to crop failures, widespread famine and mortality, and incited war.

The wiggles that make up 500 years of reconstructed Indian Ocean Dipole variability. The red triangles show when extreme positive events occurred.


As far as we can tell, this event shows just how extreme Indian Ocean Dipole variability can be, even without any additional prompting from external forces like human-caused climate change.

Why should we care?
Indian Ocean Dipole variability will continue to episodically bring extreme climate conditions to our region.
Drilling through fossilised coral layers to look into the past. Nerilie Abram
But previous studies, as well as ours, have shown human-caused climate change has shortened the gaps between these episodes, and this trend will continue. This is because climate change is causing the western side of the Indian Ocean to warm faster than in the east, making it easier for positive Indian Ocean Dipole events to establish.
In other words, drought-causing positive Indian Ocean Dipole events will become more frequent as our climate continues to warm.
In fact, climate model projections indicate extreme positive Indian Ocean Dipole events will occur three times more often this century than last, if high greenhouse gas emissions continue.
This means events like last year will almost certainly unfold again soon, and we’re upping the odds of even worse events that, through the fossil coral data, we now know are possible.
Knowing we haven’t yet seen the worst of the Indian Ocean Dipole is important in planning for future climate risks. Future extremes from the Indian Ocean will act on top of long-term warming, giving a double-whammy effect to their impacts in Australia, like the record-breaking heat and drought of 2019.
But perhaps most importantly, rapidly cutting greenhouse gas emissions will limit how often positive Indian Ocean Dipole events occur in future.

Links

(US) Companies Expect Climate Change To Cost Them $1 Trillion In 5 Years

WIRED

Many corporations see climate change posing a significant threat to their business within the decade, according to a new report.
In 2018 the US sustained $91 billion in damages from climate-related disasters, including tropical cyclones, severe storms, inland floods, droughts, and wildfires. Scott Olson/Getty Images
In January, climate change claimed its first corporate victim. Facing billions in liabilities after contributing to some of California’s deadliest and most devastating wildfires, PG&E filed for Chapter 11 bankruptcy protection. This spring, flooding in the Midwest ruined fields, grain silos, and infrastructure. The agriculture conglomerate Archer Daniels Midland reported that the floods would cost it between $50 and $60 million in the first quarter of the year.

The costs of a disturbed climate are becoming increasingly burdensome and apparent. In 2018 the US sustained $91 billion in damages from climate-related disasters, including tropical cyclones, severe storms, inland floods, droughts, and wildfires.

“Climate change is no longer a distant threat but something that is impacting economies now,” says Bruno Sarda, president of CDP North America, a nonprofit that encourages companies to report how climate change might affect them.

A growing number of companies are recognizing that fact and are now publicly reporting the effects of climate change on their businesses. A new report published Tuesday by CDP shows that 215 of the world’s biggest companies, including giants like Apple, JPMorgan Chase, Nestlé, and 3M, see climate change as a threat likely to affect their business within the next five years, with a cumulative cost of a trillion dollars.

Companies identified a range of physical risks, such as the impact of flooding or rising sea levels on distribution centers and warehouses. They also enumerated the costs of transitioning to a lower-carbon, more climate-ravaged world, including updating facilities to withstand stronger storms or use less water, and complying with potential policies that would likely raise the cost of fossil fuels.

Companies also recognized an image issue. In the report, Google's parent company, Alphabet, writes, “Not addressing climate change risks and impacts head on could result in a reduced demand for our goods and services because of negative reputation impact.”

CDP also found, however, that companies saw some opportunities in adapting to climate change. The report found that companies estimated opportunities related to climate change could bring in $2.1 trillion. Most companies pegged those benefits to the growth of low-emissions products and the creation of new products, such as new fuel sources or energy-efficient cars, which might appeal to a customer base that is increasingly climate-conscious.

The CDP report is part of a growing effort to encourage companies to be open about how climate change will affect their financial well being. In 2015 the Financial Stability Board, an international organization that studies the global financial system, formed the Task Force on Climate-Related Disclosures (TCFD).

Led by Michael Bloomberg, the Task Force has released recommendations to help companies accurately assess and disclose their climate-related risks. The TCFD also wants to help standardize how companies think about and report those risks. Similarly, a coalition of investment groups including State Street Global Advisors, BlackRock, and Vanguard are backing the Sustainability Accounting Standards Board, which helps companies report accurately on these issues.

“US companies are definitely putting out more information on how they are addressing climate change. They don’t look at an election cycle. They address this from a shareholder perspective,” says Rakhi Kumar, who leads State Street Global Advisors’ efforts on environmental investment. She says companies are hearing from investors who are worried. “That’s what they are reacting and responding to.”

Disclosure is meant to work like an x-ray, allowing customers and investors to look inside a company, see where it is vulnerable, and help it improve. By making their predictions and analyses public, companies can also learn from each other about how to become more resilient in the face of climate threats.

“Climate change is right now a very much under-priced risk in financial disclosures,” says Sarda, who believes both companies and investors need to prioritize climate-related accounting more. He suggests that better disclosure could fundamentally transform the markets. It could change how publicly traded companies are valued. Those that are more prepared or resilient would be viewed as better investments than their more vulnerable counterparts.

Sarda is confident that companies can do a lot to help combat climate change, but he and Kumar say governments also play an important role in enacting policies that will stabilize markets. “Putting a price on carbon or even a better price on water or on pollution in general is something that would create a lot of certainty for business,” says Sarda.

But that’s unlikely in the current moment, with the Trump administration rolling back federal efforts to combat climate change. Last week, The New York Times reported that US Geological Survey director James Reilly ordered the agency to stop modeling climate scenarios that predict the effects of climate change beyond 2040.

Aside from a carbon tax, Sarda suggests governments could also help standardize climate disclosures the same way they standardize traditional financial reporting, guiding companies on how to assess and evaluate potential risks.

Right now, these disclosures are also somewhat limited in that they are self-assessments and aren’t subject to any in-depth, formal audit. So far, companies’ reporting practices have also varied a lot.

Some of that variation can be attributed to the nature of the risks themselves. Companies can pretty accurately predict how much it will cost to close down a factory for two weeks because of flooding, for example. But some risks are harder to calculate. How much will changing weather patterns in the midwest alter crop yields or harm pollinators? And how will that ultimately figure into the bottom line?

Companies also have blind spots. A corporation might do a good job of assessing risks to its own physical infrastructure, but might not apply that same scrutiny to its supply chain. Kumar also notes that companies typically only plan for the short term, while investors are on the lookout for future complications. Those different time lines create a “impasse” between companies and their investors. Kumar gives the example of coal energy plants, which may be profitable in the short term but which represent a long term risk that investors want “phased out.”

Christopher Wright, a professor at the University of Sydney who has written about corporate responses to climate change, says that while efforts like the Task Force on Climate-Related Financial Disclosures have been garnering lots of attention, some of the predictions that companies make are “somewhat fanciful.”

Many companies model what the world will look like if our climate warms by 3 or even 4 degrees Celsius. But, Wright argues, warming of that magnitude would fundamentally disrupt society, not just supply chains. Those costs can’t be modeled so easily. “What of course is missing from all of this is a serious focus on implementing dramatic emissions reduction now!” he wrote in an email.

The next step, says Sarda, is for investors and customers to examine the data and start demanding accountability from companies. He says that in order to make real progress confronting climate change, we can’t wait for government-sponsored policies and regulations. For things to truly change, he says, business needs to play a key role too.

Links