^{7 October 2022}

The world is heating up. The Intergovernmental Panel on Climate Change (IPCC) says global surface temperature has increased faster since 1970 than in any other 50-year period over the last 2,000 years.

There is also growing evidence that warming temperatures are leading to a more volatile world with more extreme climate disasters. Climate change is already affecting many weather and climate extremes across the globe through heat waves, floods, droughts and cyclones.

The environmental, human and economic costs associated with these disasters are staggering, and the impacts continue to see the poorest bearing the brunt of the burden.

Informal settlement communities are at the forefront of the impacts of climate change: already located in areas prone to flooding, climate change-induced extreme weather events and sea level rise are disproportionately impacting these vulnerable communities by exacerbating the adverse conditions.

Researchers are beginning to gauge the precise impacts of climate challenges on the human experience in these vulnerable communities. Informal settlement residents are exposed to extreme heat stress in the tropics and lack means to adapt, as Emma Ramsay, RISE PhD researcher at Monash University’s Faculty of Science, explains.

‘Heat stress is chronic – these are not just one-off extremes. When measuring heat stress in informal settlements in Makassar, South Sulawesi, we found that in the context of international standards, conditions regularly exceed recommended levels for work and even rest; they approach the upper limits of human survival’.

Informal housing provides little protection from heat exposure. With less than 5% of households surveyed in Makassar having air-conditioning, ‘We can see that these residents have little capacity to adapt to heat stress,’ says Ramsay.

This point about having the means and resources to adapt is also evident in research on the impacts of flood disasters and health among the urban poor. As Michelle Escobar Carías – RISE PhD researcher at Monash University’s Faculty of Business and Economics – explains, there is a strong socio-economic gradient: ‘people in the top income quintiles – the urban wealthy – show no health effects from flood
exposure,’ says Escobar.

‘Our surveys in Makassar show not only that the urban poor experience significant increases in acute morbidities and depressive symptoms following floods, but that these negative mental health effects are detectable up to five years post-flood.

‘Part of these lasting mental health effects could be caused by financial stress caused by floods, through higher medical bills, the acquisition of debt and the depletion of household assets,’ explains Escobar.

International climate assessments show that both dry and wet extremes will continue to increase with future global warming. However, Ramsay and Escobar’s new body of knowledge provide the evidence-base to consider better-designed management strategies for urban informal settlements.

‘We need ongoing local monitoring in settlements to capture the full magnitude of climate hazards and to make accurate projections of future change,’ says Ramsay. ‘But we also already know about the cooling potential of urban green space in cities, and that increasing blue and green space may help to mitigate thermal extremes’.

For Escobar, the findings are also useful for local authorities to improve the surge capacity of the health care system, as well as economic support post-floods. ‘The connection between the financial burden caused by flood exposure and the mental health effects point to the need for financial aid instruments that local authorities could consider to reduce or prevent these negative health effects’.

This research suggests that climate adaptation is possible with strategic investments from governments and funding bodies, and when people have the right means and support systems around them.

RISE is helping meet this challenge through the introduction of water-sensitive infrastructure and facilities in settlements where flooding and contamination have created highly adverse living conditions. The world-first research trial will inform how these measures can contribute to climate adaptation and resilience for those most exposed to the impacts of climate change.