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It’s the build-up in northern Australia – the time of year when heat and humidity get worse ahead of the wet season. Common phrases such as “going troppo” or “mango madness” give a sense of the effects. Tempers fray and tensions rise.
There’s now emerging evidence that humidity makes heat more dangerous. Humid heatwaves – where high temperatures combine with high humidity – are potentially more dangerous than dry heatwaves.
Elsewhere in the world, humid heatwaves are already claiming lives. Over 1,300 pilgrims died in Saudi Arabia in 2024 due to lethal levels of humidity and heat, while India and Pakistan have also been hard hit.
Our recent research in the Northern Territory found more people came to emergency departments during intense humid heatwaves than comparable dry heatwaves.
The problem is, we’re not warning people about this combined threat. Australia’s heatwave warning systems focus only on temperature – not on humidity.
Intense heat stresses the body. Humidity can make this worse.
The human body relies heavily on sweating to regulate temperature. When sweat evaporates from the skin, it removes heat and helps keep the body cool. When humidity is high, evaporation doesn’t work as well and it’s harder for the body to release heat and stay cool.
Humid conditions can boost the risk of heat-related illnesses such as heatstroke, worsen existing heart and lung conditions and put more strain on the bodies of people with chronic diseases.
High humidity can also contribute to poor sleep, reducing the body’s ability to recover during prolonged hot periods.
Hot and wet conditions also provide optimal conditions for mosquitoes, ticks and parasites, which are vectors for the spread of key tropical diseases. Mould, bacteria and viruses are more likely to grow in high humidity, increasing the risk of lung and skin disease.
The top third of the Northern Territory has a monsoonal coastal climate prone to humidity, while the two thirds inland is arid. This means we can analyse and compare humid and dry heatwaves across these environments.
Our study analysed more than two decades of emergency department data across the NT to see if dry heat or humid heat affected the numbers of people needing emergency care. We used a temperature-based index for dry heat and a combined temperature and relative humidity index to determine humid heat.
The results were clear. While more people sought emergency treatment during both dry and humid heatwaves, humid heatwaves were worse. Severe and extreme dry heatwaves led to 4.4% more hospital visits, while similar humid heatwaves saw 6.1% more people attending emergency departments.
When arid areas of the Territory were hit by humid heatwaves, the effect was even clearer – emergency visits rose 8.7%.
In many parts of northern Australia, heatwaves are projected to become more frequent and intense due to global warming.
Every summer, Australia’s Bureau of Meteorology issues heatwave warnings to give people advance notice of three or more days of unusual heat over day and night. Warnings can be issued for mild, severe and extreme heatwaves.
These warnings are vital. They let people prepare for heat and change plans, while health services can boost staffing numbers.
The problem is, these warnings are largely based on temperature. Most people can tolerate a 35°C day with low humidity. But a 35°C day with high humidity is much harder for us to cope with.
This means the current system may not be warning Australians about a real risk to their health – especially those in tropical and coastal regions.
Health services in the NT are often ageing and under strain. Last wet season did significant damage.
Dry and wet heatwaves will put more pressure on health systems already struggling during extreme weather. Even a modest increase in patients will add more pressure on staffing, bed capacity and resources.
We’ve long known heat affects some people much more than others. Children, older adults, people with chronic diseases and those in disadvantaged communities are hit harder. In the Territory, low-quality housing, poor access to healthcare and outdoor work and recreation also boost risks from heat.
It’s no longer enough to define a heatwave using temperature alone. Across northern Australia, humidity directly affects how people experience a heatwave.
Climatologists are already exploring ways to include humidity in measures of dangerous heat.
To take the threat of humid heat seriously, we need to redefine heatwaves to include humidity and temperature. This will strengthen our early warning systems.
On a practical level, we need to prepare our health systems for more demand during severe humid heat, particularly in remote and tropical regions.
As the Top End prepares for another wet season, authorities will focus on the threats of cyclones, flooding and other visible weather threats. It’s time to look at a less visible danger – the combination of heat and humidity.
Alyson Wright, Adjunct Fellow in Public Health, Menzies School of Health Research; Mark de Souza, PhD Candidate in Sustainable Healthcare, The University of Melbourne, and Sharon Campbell, Postdoctoral Research Fellow in Environmental Health Research, University of Tasmania
This article is republished from The Conversation under a Creative Commons license. Read the original article.
The 31st Council of the Parties (COP) to the UN Framework Convention on Climate Change (UNFCCC) has its' next meeting commencing on 9 November and running until 20 November 2026. The host country is Turkiye with Antalya as the venue city. The main topics for discussion are -
Raw, grilled, roasted, stuffed – there are many ways to enjoy capsicums, also called bell peppers, sweet peppers or paprika.
Capsicums originated in Central and South America and belong to the nightshade family along with tomatoes and eggplants.
Like tomatoes, we consider capsicums a vegetable because they’re lower in sugar than most fruits and are usually eaten in savoury dishes. But botanically speaking, capsicums are a fruit – more specifically, a berry – because they develop from a flower and contain seeds.
Spicy chilli peppers such as jalapeño, bird’s eye and many others are also a type of capsicum. What makes these spicy is the molecule capsaicin, which activates heat and pain receptors on our tongue. Capsicums are sometimes called sweet peppers because they don’t contain capsaicin.
You might think green, yellow, orange and red are different types of capsicum, but they’re all actually the same fruit. All capsicums start out green, and their colour changes to yellow, then orange and finally red as they ripen.
But the difference between the colours isn’t just superficial – it affects nutrition, flavour and more.
First, let’s bust the myth that a capsicum with three bumps on the bottom is “male” and one with four bumps is “female”, and therefore sweeter. This is entirely false. Fruits don’t come with male and female parts the way flowers do. A capsicum will typically have two to five lobes (bumps). The shape mostly depends on the genetics of the plant and doesn’t affect the flavour.
But colour does affect a capsicum’s flavour because this reflects how ripe the capsicum was when it was picked.
A capsicum starts out green because it contains lots of chlorophyll, the pigment that makes plants green. Chlorophyll is the plant chemical of photosynthesis and makes energy for the capsicum to grow. As a capsicum ripens, chlorophyll breaks down and is replaced by carotenoids: yellow, orange and red pigments. Green capsicums also contain some carotenoids, but these colours are hidden by chlorophyll.
Green capsicums are ready to be picked about eight weeks after planting. Because they are not ripe, they are slightly bitter with a firm, crunchy texture. They suit stir-fries, fajitas, casseroles and add crunch to salads.
Yellow and orange capsicums are in the middle of ripening and are picked roughly two (yellow) and three (orange) weeks after green capsicums. These have a mild, sweet flavour. They are quite crisp when raw – great for adding colour to salads and lunchboxes. They soften when cooked, so are also good on the barbecue.
Red capsicums are the ripest, having stayed on the plant four weeks longer than green capsicums. They are the sweetest and richest in flavour, and the softest when cooked. They are excellent for roasting, soups and dips.
All capsicums have several health benefits and are nutrient rich. They contain lots of vitamin C and antioxidants such as flavonoids, phenolic compounds and carotenoids. Capsicums are also a good source of fibre, which supports digestive health.
But there are differences in nutritional benefits based on colour, and whether you eat the peppers raw or cooked.
Carotenoids – particularly capsanthin, beta-carotene, lutein, violaxanthin and zeaxanthin – impact the colour of capsicums based on the proportions in which they’re present. All carotenoids and chlorophyll are antioxidants, but with different health benefits.
Green, yellow and orange capsicums are rich in lutein, violaxanthin and zeaxanthin. These are essential for eye health and protect against age-related macular degeneration and cataracts.
Orange and red capsicums have the highest vitamin C and beta-carotene. Beta-carotene gets converted to vitamin A in the body, which is important for good cell health, vision, and immune and cognitive functions.
Red capsicums contain the most capsanthin, the carotenoid with the strongest antioxidant activity. This protects our body’s cells against damaging free radical chemicals.
For all capsicums, cooking increases the availability of carotenoids and polyphenols but reduces vitamin C. For the greatest nutritional benefits, it’s best to eat a combination of raw and cooked capsicums of different colours.
In fact, eating a rainbow of fruits and vegetables provides many beneficial compounds. We have measured carotenoids in the skin using a non-invasive device to assess vegetable intake, because most Australians don’t eat enough fruit and vegetables.
It’s interesting to note a capsicum’s colour can also affect its price.
Green capsicums are usually the cheapest because they’re picked earlier, which makes them cheaper to grow. Red capsicums remain on the plant the longest, increasing growing costs. However, yellow capsicums are typically the most expensive, as they’re harder to grow with a shorter picking period.
A cheaper and equally healthy option is “imperfect” capsicums. Two-toned capsicums, for example part green and part orange, provide a greater mix of different carotenoids. Malformed capsicums are only imperfect in appearance, not flavour or health benefits.
Ultimately, all capsicums, whether red, green, yellow or orange, and raw or cooked, are a nutritious choice.
Theresa Larkin, Associate Professor of Medical Sciences, University of Wollongong and Megan Hammersley, Lecturer, Public Health, University of Wollongong
This article is republished from The Conversation under a Creative Commons license. Read the original article.
Modern cities across the world were never designed for the extreme heat that climate change is now causing. Changes are needed not only in terms of building design but with the coordination of services notably emergency services. The article below provides a summary of one such approach -
In Australia, the days are growing longer and summer is fast approaching. But a very strong El Niño – a natural weather phenomenon that drives variations in temperature and winds across the Pacific – could make this summer a sweltering one.
This raises the question: are we ready for extreme heat?
Our new research examined how Australia’s Greater Sydney region is preparing for surging temperatures and more frequent heatwaves. In particular, Western Sydney is known for its stifling temperatures, at times being the hottest place on the planet.
We found this city-wide approach involves much more than simply telling people what to do when temperatures soar.
Many Australians know how to cope with hot weather. We drink plenty of water, close blinds and curtains, stay indoors when the sun is at its strongest and regularly check on family, friends and neighbours.
This is good advice. However, not everyone can act on it.
For some people, staying cool is much easier said than done. Not everyone can afford to keep the air conditioner running. Not everyone has a well-insulated home, particularly those living in older homes. Not everyone is well-connected to their neighbours and wider community.
This raises several crucial questions:
how can we protect those most vulnerable to extreme heat, including the elderly, pregnant women and people with existing health conditions?
how should we design houses, streets and neighbourhoods to reduce heat exposure in the first place?
where else can residents go if they need relief from soaring temperatures?
Our latest research took a closer look at how one city is preparing for extreme heat.
The Greater Sydney Heat Taskforce, established in 2023 and led by the Western Sydney Regional Organisation of Councils and Resilient Sydney, aims to help nearly 5.6 million Sydneysiders cope with rising temperatures.
This taskforce brought together 373 representatives from more than 40 organisations across government, health, emergency services and other sectors. Over an 18-month period, these representatives developed the Greater Sydney Heat Smart City Plan. The plan was launched in December 2024 and is now being implemented.
The plan sets out 40 recommendations for action between 2025 and 2030. These cover topics such as raising awareness about heat-related risks, designing cooler homes and neighbourhoods and protecting vulnerable communities.
The plan also underscores the need for better coordination of services and emergency responses. Unlike floods and bushfires, which trigger specific, established emergency actions, extreme heat has historically fallen between different areas of government.
As researchers working within the taskforce, we examined how the Heat Smart City Plan helped bridge these gaps and identified ways to turn its recommendations into action.
Here are our three main findings.
Coordination is key
To create an effective plan, the Greater Sydney Heat Taskforce had to overcome organisations working in silos. For example, health agencies focus on heat-related illness, while councils manage how public spaces and planning authorities shape the built environment. This means responses to heat risk are often fragmented. By contrast, the Heat Smart City Plan helped organisations build trust, clarify responsibilities and identify gaps in governance.
Communities must be involved
By engaging community groups, including Sweltering Cities and the Western Sydney Community Forum, the taskforce built community experiences into the plan. This boosted support for initiatives like Extreme Heat Awareness Day.
Collaboration alone isn’t enough
Long-term funding, clear responsibilities and ongoing support from local institutions are key to the success of any city-wide heat plan. The Heat Smart City Plan identifies the lead organisation responsible for turning recommendations into action. We found this encouraged organisations to take ownership and incorporate heat preparedness into existing planning, emergency management and climate adaptation frameworks.
The NSW government, for instance, is exploring how urban greening, improved shade and heat-sensitive building design can be incorporated into planning through its draft State Environmental Planning Policy.
The Greater Sydney Heat Smart City Plan is a step forward, but the challenge now is turning its ambitions into practical, lasting changes across government and industry.
Promising initiatives already exist. The Australian Red Cross’s TeleRedi program, currently run in South Australia and Western Australia, sees volunteers check in on vulnerable people during dangerous weather.
In Blacktown, libraries and other air-conditioned public facilities offer places to escape the heat, as outlined in the council’s Beat the Heat guidance.
These initiatives are not complicated or new. But making them available where needed requires long-term funding and coordination across housing, infrastructure, health and emergency services. Only then can we protect lives and communities in a warming world.
We’d like to thank Kerry Robinson (Greater Sydney Heat Taskforce Chair), Judith Bruinsma and Kelly Gee (Western Sydney Regional Organisation of Councils, WSROC) and Melinda Dewsnap (Resilient Sydney) for facilitating the taskforce, alongside all its members. We particularly recognise the late Charles Casuscelli, former CEO of WSROC, whose leadership was instrumental in driving this work forward.
Nicky Morrison, Professor of Planning and Director of Urban Transformations Research Centre, Western Sydney University; Patrick Harris, Associate professor, UNSW International Centre for Future Health Systems, UNSW , and Vanita Yadav, Senior Research Fellow, Urban Transformations Research Centre, Western Sydney University
This article is republished from The Conversation under a Creative Commons license. Read the original article.
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Its Halloween this month, therefore timely to outline key information about this event -
Halloween is observed on 31 October each year, drawing on both ancient Celtic tradition and the Christian calendar. Its earliest antecedent is usually traced to Samhain, a Gaelic festival marking the end of the harvest and the start of winter. Medieval Irish sources describe Samhain as a time when the boundary between the living and the otherworld was believed to weaken, and communities marked it with feasts and bonfires.
The Christian connection comes through All Saints’ Day, a feast honouring saints and martyrs. By the ninth century it was observed on 1 November throughout the Western Church, and the evening before became known as All Hallows’ Eve, later shortened to Halloween. All Souls’ Day, on 2 November, was established around AD 1000 as a day of prayer for the dead. Together these observances formed a three-day period centred on remembrance.
Historians continue to debate how directly Samhain shaped the Christian feasts. Some scholars see a deliberate overlay of Christian observance on older customs. Others note that written accounts of Samhain date only from the early medieval period, were recorded by Christian scribes, and say little about practice before conversion, so a direct line from pre-Christian ritual to the Christian feasts cannot be demonstrated.
Many familiar practices developed in Ireland, Scotland and parts of England between the medieval and early modern periods. Souling was a custom in which the poor visited households on All Hallows’ Eve, offering prayers for the dead in exchange for soul cakes, small spiced cakes given as alms. Guising, in which people wore disguises and performed songs or tricks in return for food or coins, is recorded in Scotland from at least the sixteenth century, often at New Year. Halloween guising in Scotland and Ireland is well documented in nineteenth-century accounts. Bonfires and divination games, often using apples and nuts to predict future marriages, were also common.
Lanterns carved from turnips and other root vegetables were used to ward off spirits. The name jack-o’-lantern is linked to an Irish folk tale about a man known as Stingy Jack. In North America, where pumpkins were plentiful and easier to carve, they largely replaced turnips.
In the United States, Halloween is largely a secular and commercial occasion. Irish and Scottish immigrants, particularly during the nineteenth century, helped establish its customs there. Trick-or-treating became widespread by the mid-twentieth century and is now central to the event, alongside costumes, pumpkin carving, decorated homes, parties and themed attractions.
In Europe, practice varies by region. Ireland and the United Kingdom retain the closest links to the older customs, with costumes, children’s door-to-door visits, fireworks and bonfire events in some areas. In much of continental Europe, Halloween is a more recent import, growing in popularity since the 1990s through American film, television and retail. Traditional observance there centres on All Saints’ Day on 1 November, a public holiday in countries including France, Italy, Spain, Austria and Poland. Families visit cemeteries to place flowers and candles on graves.
Happy Halloween !
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