Flood

• Now we get flash floods much further inland, such as Broken Hill in 2012 and 2022 and Cobar, Bourke and Nyngan in 2022.
• Flash floods are those beginning between one and six hours after rainfall, while riverine floods take longer to build.
• Instead, we’re seeing warm, moist air pushed down from the Coral Sea, leading to thunderstorms and floods much further inland.

What’s changing?

• Inland, flash floods occur when intense rain hits small urban catchments, runs off roads and concrete, and flows into low-lying areas.
• Early this month, the subtropical jet stream changed its course, triggering a cyclonic circulation higher in the atmosphere over inland eastern Australia.
• The result was localised extremely heavy rain, which led to the Warragamba Dam spilling and flood plain inundation in western Sydney.
• These are characterised by a deepening coastal trough and upper-level low pressure systems further west, over inland eastern Australia.
• Instead, flash floods occurred when slow-moving upper-level low pressure circulations encountered air masses laden with moisture evaporating off the oceans.

Haven’t there always been flash floods?

• Previously, inland floods tended to come after long periods of widespread rain saturated large river catchments.
• Inland flash floods were not so common and powerful as in recent decades.
• What about the famous inland floods which move through Queensland’s Channel Country and fill Kati Thanda/Lake Eyre?
• These are slow moving riverine floods, not flash floods.

Read more:
Changes in the jet stream are steering autumn rain away from southeast Australia

Short, intense rain bursts are going global

• Dubai this week had a year’s rain (152 mm) in a single day, which triggered flash floods and caused widespread disruption of air travel.
• Other parts of the United Arab Emirates got even more rain, with up to 250 mm.
• In Western Australia’s remote southern reaches, the isolated community of Rawlinna recently had 155 mm of rain in a day.

The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.

• Human-induced climate change made the severe 2015–2017 drought three to six times more likely.
• Our new report on Climate Change Impacts in South Africa has found that as Earth warms, people living in South Africa will face reduced incomes, less food and water security and a higher cost of living.
• Our findings, based on a synthesis and review of existing research on climate change, are that climate change and socioeconomic risks threaten to bring about a huge change to this status.
• Combating the impacts of climate change in South Africa requires adaptive measures, such as changing the way we farm, coordination by the government and international commitment to reduce emissions.

Heatwaves

• Farm workers will be exposed to more extreme temperatures working outside and others will suffer from heat stress in their living and working environment.
• Here's how

  Extreme weather threatens the plants and animals that attract tourism, and directly damages infrastructure at nature reserves, adventure destinations and parks.

• Rising temperatures are projected to reduce visitor numbers to South Africa’s national parks by 4% by 2050, affecting the Kruger National Park most.

An agricultural crisis

• Smallholder farms are often located in areas with less fertile soils or limited infrastructure, leaving these farmers more vulnerable to climate change.
• Arable land suitable for growing crops is concentrated in just 12% of South Africa’s land area.
• Therefore, any extreme event that reduces production – such as drought – can be expected to reduce job security and income for farming households and agricultural workers.

Water

• Drought and floods damage transport links, public buildings, and water and energy infrastructure, and challenge the provision of basic services.
• During the water crisis that followed the 2015–2017 drought, for example, reservoirs serving 3.7 million people around Cape Town dropped to 20% of capacity, leading the government to impose water restrictions.

An increase in gender-based violence

• These gender inequalities include a high incidence of gender-based violence and a higher likelihood of poverty among women.
• Research in other parts of the world has also linked rising temperatures with an increase in gender-based violence.

Solutions

Much of the country’s economic future hinges on the speed with which investments in renewable energy can replace coal and provide affordable and reliable electricity. Slowing down climate change will take a huge global effort and progress has been limited. The only alternative is to be prepared and adapt to the projected changes.
Peter Johnston receives funding from United Nations, NORCE, NRF

• Stock market development and familiarity (language and distance) are considered key determinants for home bias.
• The literature neglects however that investors often invest in foreign funds domiciled in financial centers.

• Global insured losses from natural catastrophes outpaced global economic growth over the past 30 years: From 1994 to 2023, inflation-adjusted insured losses from natural catastrophes averaged 5.9% per year, while global GDP grew by 2.7%.
• 2023 was also marked by a high frequency of events as 142 insured natural catastrophes set a new record.
• Hailstorms are by far the main contributor to insured losses from SCS, responsible for 50–80% of all SCS-driven insured losses.
• Global insured losses from SCS accumulated to a new record of USD 64 billion globally in 2023, 85% originating in the US.