Australia Is Heading Toward an Unprecedented Megadrought

0:00A mega drought might hit Australia soon, and this isn't just about a couple of dry seasons. We're talking about 20 years of little or no rain. While Australia could be facing the longest and most devastating droughts, since official records began, the rest of the world might struggle to buy bread, flour, or cereals. Energy prices are likely to spike globally, and neighboring countries like New Zealand, Indonesia, and Malaysia must be prepared to receive Australians directly affected by the lack of water. To truly understand how severe this situation could become, we should first examine past disasters. First off, Australia is no stranger to droughts, and this phenomenon can happen across their entire territory. From 2017 to 2019, the southeast part of the country went through what they called the Tinder Box drought. This was a severe bone dry event where the cooler months saw only about half the usual rainfall. Parts of Australia became so dry that wildfires were a constant threat.

1:04Crops fail, and water was scarce. This drought was also thought to have contributed to the black summer fire disaster. By the end of 2019, bush fires were raging across the country on a scale never seen before, with people describing them as rivers of lava flowing down from treetops. The losses were staggering. The tourist industry alone took ahead of $2.8 billion, and over 7,000 jobs disappeared as a result of this difficult period. The Tinder Box drought was a big reminder of what Australia might face in the future. That's why it's so important to understand what happened in the past to get a full picture of a possible 20-year mega drought. But there is one problem, even though droughts are relatively common in Australia. The rainfall data available until today isn't enough for researchers to predict the future, and our records only go back to around 1900. So experts decided to study tree rings to uncover missing environmental data.

2:08If you look at a tree stump, you'll notice concentric rings on its surface. As trees grow, they form new rings, and the thickness of these rings depends on how much water they get. During a mega drought, the rings appear thinner because the trees don't have much water. Unfortunately, these natural records usually only go back a few hundred years, and it only tells us about specific local conditions, not the situation across all of Australia. So experts turned to computer models to simulate how Earth's climate changed from the year 850 to 2000. This approach helped them to paint a picture of when mega droughts might have occurred in Australia, and how to predict what might happen in the future. But what they were really interested in was whether the human factor might be making this scenario worse over the years, and if we are somehow intensifying these dry periods. So, are we to blame for these mega droughts?

3:08The short answer is we're not sure yet. On one hand, dry periods in Australia do seem to last longer than they did before factories and machines became common. On the other hand, they don't seem to be getting more intense or happening more often than before industrial times. This means a drought lasting 20 years might not be directly linked to human activities. Actually, this kind of phenomenon is just a normal part of how rainfall changes in Australia over time. This is backed up by evidence from ice cores, which suggests that a 39-year drought hit eastern Australia around 800 years ago. What makes it also fascinating is that there isn't just one cause for this phenomenon. I mean, there is no single mechanism that explains all cases of mega droughts. It happens because the right combination of ocean and atmospheric conditions come together and you end up with a drought. And just by random chance, you might have periods where there are 100-year-long droughts.

4:13Despite what many people think, mega droughts are not geographically isolated. They have occurred on every continent except Antarctica over the past 2,000 years and are often linked to natural events. For instance, mega droughts in North America and Southwest South America were driven by El Niño, where the Pacific Ocean near the equator gets warmer than usual, disturbing normal weather patterns. They are not rare events either. In fact, the U.S. Southwest has been experiencing a mega drought since 2000. It's being considered the driest period in 1,200 years for the region. Major reservoirs like Lake Mead and Lake Powell are at low levels. Heat waves are hitting cities like Phoenix and Las Vegas harder than ever. And wildfires are happening more frequently as the land gets drier. Now, let's think about the future. Even though we have a very recent and concrete example from the U.S., research can't exactly predict how a 20-year mega drought would play out in Australia.

5:17Usually, such events show up mainly as reduced rainfall and snowfall. But in most areas, the increase in drought risk will be caused by a warmer, more arid atmosphere. So, the ground will probably look parched and cracked, rivers and lakes will likely shrink, and the sky will be relentlessly clear and blue with barely a cloud in sight. Farmers might struggle to grow crops, making grocery prices rise worldwide. Things like bread, flour and cereals may become scarcer, as Australia supplies about 13% of global weed exports. Coal mines might be affected as they depend on water for extraction, washing and processing. That might drive up power costs for industries around the world, which could be passed on to consumers, impacting global growth and inflation. As cities might face water shortages, Australians will likely find new ways to conserve every drop or may be moved to New Zealand or Southeast Asia.

6:18Now, you're probably thinking, when is this big event going to happen? Honestly, it's really hard to predict exactly. Mega droughts can happen every 150 to 1000 years, but experts think Australia should be ready for one to happen in the next 10 years or so. And this possibly should be taken seriously. This phenomenon has been known to contribute to the collapse of entire civilizations. Take the Acadians of Mesopotamia, who built the world's first empire more than 4000 years ago. Studies of moisture at the ruins of Acadian cities suggest that they experienced a massive drought lasting 300 years, and this may have led to their collapse. A similar thing happened to the Assyrian Empire, which existed over 2,700 years ago, in what is now northern Iraq. For years, it was a real mystery why they left their capital of Nineveh and never returned. But recent studies of a stalagmite in the Kunabakh Cave revealed that the rise and fall of the empire coincided with a wet period,

7:23followed by a 125-year-long mega-draft, because they were very dependent on seasonal rain for agriculture. This dry period made their life much harder. Even though experts now believe they probably left because of the dryness, the question of where they went is still a mystery. So, yep, mega droughts may have played a role in the collapse of great civilizations in the past. But on the positive side, we've come a long way since then, and recent climate technologies can help us prepare for events like this. Now that we know a 20-year mega-draft is very much possible, and might happen soon, Australia has some time to get ready for it. Developing strong water management plans to mitigate the sphere impacts of a mega-draft is more than necessary, and it's also important to create community support networks to provide emotional and financial support to people, particularly farmers who are more affected directly by this event. If initiatives like these emerge in the coming years, those 20 years of drought could be less intense than most people might expect.