Environment - Climate Change - COP30 - Brazil - Expectations

 

Geopolitics, backsliding and progress: here’s what to expect at this year’s COP30 global climate talks

The Amazonian city of Belém, Brazil. Ricardo Lima/Getty

Jacqueline Peel, The University of Melbourne

Along with delegates from all over the world, I’ll be heading to the United Nations COP30 climate summit in the Brazilian Amazon city of Belém. Like many others, I’m unsure what to expect.

This year, the summit faces perhaps the greatest headwinds of any in recent history. In the United States, the Trump administration has slashed climate science, cancelled renewable projects, expanded fossil fuel extraction and left the Paris Agreement (again). Trump’s efforts to hamstring climate action have made for extreme geopolitical turbulence, overshadowing the world’s main forum for coordinating climate action – even as the problem worsens.

Last year, average global warming climbed above 1.5°C for the first time. Costly climate-fuelled disasters are multiplying, with severe heatwaves, fires and flooding affecting most continents this year.

Climate talks are never easy. Every nation wants input and many interests clash. Petrostates and big fossil fuel exporters want to keep extraction going, while Pacific states despairingly watch the seas rise. But in the absence of a global government to direct climate policy, these imperfect talks remain the best option for coordinating commitment to meaningful action.

Here’s what to keep an eye on this year.

A smaller-than-usual COP?

A persistent criticism of the annual climate summits is that they have become too big and unwieldy – more a trade show and playground for fossil fuel lobbyists than an effective forum for multilateral diplomacy and action on climate change. One solution is to deliberately make these talks smaller.

The Belém conference may end up having a smaller number of delegates, though not by design so much as logistical headaches.

Brazilian President Luiz Inácio Lula da Silva backed the decision to invite the world to the Amazon to display how vital the massive rainforest is as a carbon sink. But Belém’s remote location on the northeast coast, limited infrastructure and shortage of hotels have seen prices soar, putting the conference out of reach for smaller nations, including some of the most vulnerable. These constraints could undermine the inclusive “Mutirão” (collective effort on climate change) sought by organisers.

Many delegates will sleep on ships at the Belem climate talks. Pictured is Curupira, a figure from Brazilian folklore and the COP30 mascot. Gabriel Della Giustina/COP30, CC BY-NC-ND

Show me the money

Climate finance is a perennial issue at COP meetings. These funding pledges by rich countries are intended to help poorer countries reduce emissions, adapt to climate change or recover from climate disasters. Poorer countries have long called for more funding, given rich countries have done vastly more damage to the climate.

At COP29 in Baku, Azerbaijan last year, a new climate finance goal was set for US$300 billion (~A$460 billion) to be raised annually by developed countries by 2035, with the goal of reaching $US1.3 trillion (~A$2 trillion) in funding from both government and private sources over the same period.

To deliver the second goal, negotiators laid out a “Baku to Belém” roadmap. The details are due to be finalised at COP30. But with the US walking away from climate action and the European Union wavering, many eyes will be on China and whether it will step into the climate leadership vacuum left by developed countries. The EU has only just reached agreement on a 2040 emissions reduction target and an “indicative” cut for 2035.

Climate finance will be the priority for many countries, as worsening disasters such as Hurricane Melissa in Jamaica and Typhoon Kalmaegi in the Philippines once again demonstrate the enormous human and financial cost of climate change.

The latest UN assessment indicates the need for this funding is outpacing flows by 12–14 times. In Belém, poorer countries will be hoping to land agreement on greater finance and support for adaptation. Work on a global set of indicators to track progress on adaptation – including finance – will be key.

Brazilian organisers hope to rally countries around another flagship funding initiative set to launch at COP30. The Tropical Forests Forever Facility would compensate countries for preserving tropical forests, with 20% of funds directed to Indigenous peoples and local communities who protect tropical forest on their lands. If it gets up, this fund could offer a breakthrough in tackling deforestation by flipping the economics in favour of conservation and protecting a huge store of carbon.

2035 climate pledges

Belém was supposed to be a celebration of ambitious new emissions pledges which would keep alive the Paris Agreement goal of holding warming to 1.5°C. Nations were originally due to submit their 2035 pledges (formally known as Nationally Determined Contributions) by February, with an extension given to September after 95 per cent of countries missed the deadline.

When pledges finally arrived in September, they were broadly underwhelming. Only half the world’s emissions were covered by a 2035 pledge, meaning the remaining emissions gap could be very significant. Australia is pledging cuts of 62–70% from 2005 emissions levels.

That’s not to say there’s no progress. A new UN report suggests countries are bending the curve downward on emissions but at a far slower pace than is needed.

How negotiators handle this emissions gap will be a litmus test for whether countries are taking their Paris Agreement obligations seriously.

Rise of the courts

Even as some countries back away from climate action, courts are increasingly stepping into the breach. This year, the International Court of Justice issued a rousing Advisory Opinion on states’ climate obligations under international law, including that national targets have to make an adequate contribution to meeting the Paris Agreement’s temperature goal. The court warned failing to take “appropriate action” to safeguard the climate system from fossil fuel emissions – including from projects carried out by private corporations – may be “an internationally wrongful act”. That is, they could attract international liability.

It will be interesting to see how this ruling affects negotiating positions at COP30 over the fossil fuel phase-out. At COP28 in 2023, nations promised to begin “transitioning away from fossil fuels in energy systems”. If countries fail to progress the phase-out, accountability could instead be delivered via the courts. A new judgement in France found the net zero targets of oil and gas majors amount to greenwashing, while lawsuits aimed at making big carbon polluters liable for climate damage caused by their emissions are in the pipeline.

An Australia/Pacific COP?

A big question to be resolved is whether Australia’s long-running bid to host next year’s COP in Adelaide will get up. The bid to jointly host COP31 with Pacific nations has strong international support, but the rival bidder, Turkey, has not withdrawn.

If consensus is not reached at COP30, the host city would default back to Bonn in Germany, where the UN climate secretariat is based.

Outcome unknown

As climate change worsens, these sprawling, intense meetings may not seem like a solution. But despite headwinds and backsliding, they are essential. The world has made progress on climate change since 2015, due in large part to the Paris Agreement. What’s needed now on its tenth anniversary is a reinfusion of vigour to get the job done.

Jacqueline Peel, Professor of Law, The University of Melbourne

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Health - research finds genes act differently in the brains of men and women

 

Hundreds of genes act differently in the brains of men and women

GettyImages. Tek Image / Science Photo Library via Getty Images

Jenny Graves, La Trobe University

Differences between men and women in intelligence and behaviour have been proposed and disputed for decades.

Now, a growing body of scientific evidence shows hundreds of genes act differently in the brains of biologically male or female humans. What this means isn’t yet clear, though some of the genes may be linked to sex-biased brain disorders such as Alheizmer’s and Parkinson’s diseases.

These sex differences between male and female brains are established early in development, so they may have a role in shaping brain development. And they are found not only in humans but also in other primates, implying they are ancient.

Gene activity in male and female brains

Decades of research have confirmed differences between men and women in brain structure, function and susceptibility to mental disorders.

What has been less clear is how much of this is due to genes and how much to environment.

We can measure the influence of genetics by looking directly at the activity of genes in the brains of men and women. Now that we have the full DNA sequence of the human genome, it is comparatively easy to detect activity of any or all of the roughly 20,000 genes it contains.

Genes are lengths of DNA, and to be expressed their sequence must be copied (“transcribed”) into messenger RNA molecules (mRNA), which are then translated into proteins – the molecules that actually do the work that underpins the structure and function of the body.

So by sequencing all of this RNA (called the “transcriptome”) and lining up the base sequences to the known genes, we can measure the activity of every gene in a particular tissue – even an individual cell.

When scientists compared the transcriptomes in postmortem tissue samples from hundreds of men and women in 2017, they found surprisingly different patterns of gene activity. A third of our 20,000 genes were expressed more in one sex than the other in one or several tissues.

The strongest sex differences were in the testes and other reproductive tissues, but, surprisingly, most other tissues also showed sex biases. For instance, a subsequent paper showed very different RNA profiles in muscle samples from men and women, which correspond to sex differences in muscle physiology.

A study of brain transcriptomes published earlier this year revealed 610 genes more active in male brains, and 316 more active in female brains.

What genes show sex bias in the brain?

Genes on the sex chromosomes would be expected to show different activity between men (with an X chromosome and a Y chromosome) and women (with two X chromosomes). However, most (90%) sex-biased genes lie on ordinary chromosomes, of which both males and females have two copies (one from mum, one from dad).

This means some sex-specific signal must control their activity. Sex hormones such as testosterone and oestrogen are likely candidates, and, indeed, many sex-biased genes in the brain respond to sex hormones.

How are sex differences established in the brain?

Sex differences in brain gene activity appear early in the development of the foetus, long before puberty or even the formation of testes and ovaries.

Another 2025 study examined 266 post mortem fetal brains and found more than 1,800 genes were more active in males and 1,300 in females. These sets of sex-biased genes overlapped with those seen in adult brains.

This points to direct genetic effects from genes on the sex chromosomes, rather than hormone-driven differences.

Do these differences mean male and female brains work differently?

It would be remarkable if sex differences in the activity of so many genes were not reflected in some major differences in brain function between men and women. But we don’t know to what extent, or which functions.

Some patterns are emerging. Many female-biased genes have been found to encode neuron-associated processes, whereas male-biased genes are more often related to traits such as membranes and nuclear structures.

Many genes are sex-biased only in particular sub-regions of the brain, which suggests they have a sex-specific function only in those regions.

However, differences in RNA levels don’t always produce differences in proteins. Cells can compensate to maintain protein balance, meaning that not all RNA differences have functional outcomes. Sometimes, developmental processes differ between sexes but lead to the same end result.

Brain health

Of particular interest is the finding of a relationship between sex biases and sex differences in the susceptibility to some brain disorders.

Many genes implicated in Alzheimer’s disease are female-biased, perhaps accounting for the doubled incidence of this disease in women. Studies on rodents imply that expression of the male-only SRY gene in the brain exacerbates Parkinson’s disease.

Evolution of sex differences in brain gene function

These sex-biased gene expression patterns are by no means unique to humans. They have also been found in the brains of rats and mice as well as in monkeys.

The suites of male- and female-biased genes in monkeys overlap significantly with those of humans, implying that sex biases were established in a common ancestor 70 million years ago.

This suggests that natural selection favoured gene actions that promoted slightly different behaviours in our male and female primate ancestors – or perhaps even further back, in the ancestor of all mammals, or even all vertebrates.

In fact, sex differences in the expression of genes in the developing brain look to be ubiquitous in animals. They have been observed even in the humble nematode worm.

Jenny Graves, Distinguished Professor of Genetics and Vice Chancellor's Fellow, La Trobe University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Sentinel Owl - geographical access for October 2025

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Sentinel Owl access data for October 2025:

Total page access since blog inception: 594,206

30 day total: 40.4k

Top 10 countries accessing the blog in October 2025 (actual numbers):

• Singapore: 18.9k
• United States: 6.94k
• Hong Kong: 4.85k
• Brazil: 3.16k
• Mexico: 1.33k
• India: 825
• Argentina: 335
• Indonesia: 216
• Ecuador: 159
• Malaysia: 144

Halloween - 2025

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The night of October 31st each year is Halloween, a celebration on the eve of the Christian feast of All Hallows' Day and the beginning of the period of observance of AllHallowtide (incorporating álso All Saints Day and All Souls Day). This period of dedicated to remembering the dead including notably saints, martyrs and the faithful departed. Over the past 100 years the celebration was moved into more of a cultural festival of horror, supernatural events, spectres and the macabre. Now it's essentially a children's event involving costumes, dressups, props and various ghoulish spectacles plus trick or treating. A very strong commercial element underpins the identity of Halloween.

From where does Halloween originate ? Most likely Gaelic or Celtic festivals or a separate specified religious holiday for a vigil period. There is no one agreed origin for Halloween. What is known is that the celebration originates from Ireland and Scotland and was taken across to North America by immigrants from these countries. Through American influence, the custom thereon gained wider practice to other countries in the 20th Century onwards.

Trick-or-treating is an activity where children vist homes in their residential area dressed in costumes asking for treats such as sweets and candies (although at various times it has included money). Children ask 'trick or treat? 'Treat' refers to sweets while the reference to 'trick' implies the threat of mischief to the householder or their property if there are no treats. 

Happy Halloween !

Retail shop display 2025 (c) Sentinel Owl 

Health - is gluten always the problem in food ?

                                       Gluten containing foods                    Shutterstock             

In recent decades, considerable attention has been paid to diet and gluten intolerance which can cause various health conditions such as celiac disease, wheat allergy, inflammatory and related autoimmune reactions in the intestines and bowel. Symptoms include bloating, headaches and fatigue. There is also a risk of intestinal damage occuring being a much more serious risk for some people.

What is Gluten ? it's a protein found in wheat, barley, and rye. Foods that contain it include many common baked goods such as breads, pastas, and cereals. Other sources are processed foods like some soy sauces, gravies, and beer, as well as some meat substitutes and condiments. Examples of foods containing gluten are listed below:

• Breads, bagels and flatbreads
• Cakes, cookies, muffins and pastries
• Crackers and pretzels
• Pancakes and waffles
• Pizza crusts and breadcrumbs
• Pasta and noodles 
• Beer and malted beverages
• Many soups, sauces, gravies and dressings
• Soy sauce
• Wheat (including spelt. farro, durum, seminola and couscous)
• Barley
• Rye
• Malt

Recent research reveals gluten may not always be the problem 

Recent research published in The Lancet has found that gluten may not always be the problem despite the symptoms identified being suggestive that it is. A joint review led by Associate Professor Jessica R Biesiekierski involving researchers in Australia, the UK, Italy and the Netherlands found that many people who felt unwell after eating gluten reacted equally to a placebo, or were sensitive to something else, such as fermentable carbohydrates (referred to a FODMAPS) that are found in onions, wheat and other foods.

The paper notes " Although approximately 10% of adults worldwide self-report gluten or wheat sensitivity, meta-analyses suggest that, during controlled challenge studies, 16-30% of these individuals have symptoms specifically triggered by gluten.... current evidence suggests that fermentable carbohydrates and nocebo effects contribute considerable to symptom generation in many cases".

This raises the question that for the remaining 70%, gluten may not be the cause at all but rather other factors such as FODMAPS.

The research paper can be located at this link: The Lancet - Non-coeliac gluten sensitivity

Climate Change and increasing wildfires worldwide

The climate crisis is fuelling extreme fires across the planet

Hamish Clarke, The University of Melbourne

We’ve all seen the alarming images. Smoke belching from the thick forests of the Amazon. Spanish firefighters battling flames across farmland. Blackened celebrity homes in Los Angeles and smoked out regional towns in Australia.

If you felt like wildfires and their impacts were more extreme in the past year – you’re right. Our new report, a collaboration between scientists across continents, shows climate change supercharged the world’s wildfires in unpredictable and devastating ways.

Human-caused climate change increased the area burned by wildfires, called bushfires in Australia, by a magnitude of 30 in some regions in the world. Our snapshot offers important new evidence of how climate change is increasing the frequency and severity of extreme fires. And it serves as a stark reminder of the urgent need to rapidly cut greenhouse gas emissions.

The evidence is clear – climate change is making fires worse.

A view of the Palisades fire zone in Los Angeles, where climate change fuelled the fires in January. Allen J. Schaben/Getty

Clear pattern

Our study used satellite observations and advanced modelling to find and investigate the causes of wildfires in the past year. The research team considered the role that climate and land use change played, and found a clear interrelationship between climate and extreme events.

Regional experts provided local input to capture events and impacts that satellites did not pick up. For Oceania, this role was played by Dr Sarah Harris from the Country Fire Authority and myself.

In the past year, a land area larger than India – about 3.7 million square kilometres – was burnt globally. More than 100 million people were affected by these fires, and US$215 billion worth of homes and infrastructure were at risk.

Not only does the heating climate mean more dangerous, fire-prone conditions, but it also affects how vegetation grows and dries out, creating fuel for fires to spread.

In Australia, bushfires did not reach the overall extent or impact of previous seasons, such as the Black Summer bushfires of 2019–20. Nonetheless, more than 1,000 large fires burned around 470,000 hectares in Western Australia, and more than 5 million hectares burned in central Australia. In Victoria, the Grampians National Park saw two-thirds of its area burned.

In the United States, our analysis showed the deadly Los Angeles wildfires in January were twice as likely and burned an area 25 times bigger than they would have in a world without global warming. Unusually wet weather in Los Angeles in the preceding 30 months contributed to strong vegetation growth and laid the foundations for wildfires during an unusually hot and dry January.

In South America, fires in the Pantanal-Chiquitano region, which straddles the border between Brazil, Bolivia and Paraguay, were 35 times larger due to climate change. Record-breaking fires ravaged parts of the Amazon and Congo, releasing billions of tonnes of carbon dioxide.

Protestors march for climate justice and against wild fires affecting the entire country in Sao Paulo, Brazil. Faga Almeida/Getty

Not too late

It’s clear that if global greenhouse gas emissions continue to rise, more severe heatwaves and droughts will make landscape fires more frequent and intense worldwide.

But it’s not too late to act. We need stronger and faster climate action to cut fossil fuel emissions, protect nature and reduce land clearing.

And we can get better at responding to the risk of fires, from nuanced forest management to preparing households and short and long-term disaster recovery.

There are regional differences in fires, and so the response also need to be local. We should prioritise local and regional knowledge, and First Nations knowledge, in responding to bushfire.

Action at COP30

Fires emitted more than 8 billion tonnes of carbon dioxide in 2024–25, about 10% above the average since 2003. Emissions were more than triple the global average in South American dry forests and wetlands, and double the average in Canadian boreal forests. That’s a deeply concerning amount of greenhouse pollution. The excess emissions alone exceeded the national fossil fuel CO₂ emissions of more than 200 individual countries in 2024.

Next month, world leaders, scientists, non-governmental organisations and civil society will head to Belem in Brazil for the United Nations annual climate summit (COP30) to talk about how to tackle climate change.

The single most powerful contribution developed nations can make to avoid the worst impacts of extreme wildfires is to commit to rapidly cutting greenhouse gas emissions this decade.

Hamish Clarke, Senior Research Fellow, The University of Melbourne

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Climate change - when rainforests are no longer carbon sinks - the Australian example

A crucial store of carbon in Australia’s tropical forests has switched from carbon sink to carbon source

Hannah Jayne Carle, Australian National University; Adrienne Nicotra, Australian National University; David Bauman, Institut de recherche pour le développement (IRD); Michael N Evans, University of Maryland, and Patrick Meir, Australian National University; University of Edinburgh

One approach to help fight climate change is to protect natural forests, as they absorb some atmospheric carbon released by burning fossil fuels and store large volumes of carbon.

Our new research on Australia’s tropical rainforests challenges the assumption that they will keep absorbing more carbon than they release.

We found that as climate change has intensified over the past half-century, less and less carbon has been taken up and converted to wood in the stems and branches of the trees in these forests. Woody biomass is a large and relatively stable store of carbon in forests, and acts as an important indicator of overall forest health.

The effect has been so pronounced that the woody biomass of these forests has gone from being a carbon sink to a carbon source. This means carbon is being lost to the atmosphere due to trees dying faster than it is being replaced by tree growth.

This is the first time woody biomass in tropical forests has been shown to switch from sink to source. Our research indicates the shift likely happened about 25 years ago.

It remains to be seen whether Australian tropical forests are a harbinger for other tropical forests globally.

What did we find?

Since 1971, scientists have tracked around 11,000 trees in 20 tracts of tropical rainforest in Australia’s far northeast, now part of the Queensland Permanent Rainforest Plots Network. This 49-year research effort is one of the world’s longest and most comprehensive of its kind.

We analysed this long-term data and found a clear signal: woody biomass switched from being a carbon sink to a carbon source about 25 years ago.

Why? One reason: trees are dying twice as fast as they used to.

Tropical rainforest tree species are adapted to generally warm, wet conditions. As the climate changes, they are subjected to increasingly extreme temperatures and drier conditions.These kinds of extreme climate events can damage wood and leaves, limiting future growth and leading to higher rates of tree death.

We also found tree deaths from cyclones reduced how much carbon these forests could absorb. Cyclones in far north Queensland are projected to become increasingly severe under climate change. They are also likely to push further south, potentially affecting new areas of forest.

Isn’t carbon dioxide plant food?

Burning fossil fuels and other human activities have increased carbon dioxide levels in the atmosphere. This should make it easier for plants to absorb CO₂ from the air, photosynthesise and grow. Given this, Earth system models predict higher atmospheric CO₂ levels will stimulate plant growth and increase how much carbon tropical forests can take up.

Also, remote sensing shows the canopies of tropical forests on Australia’s east coast are about 20% greener than they were in the 1980s. This suggests forest canopy growth has increased due to higher levels of CO₂ in the atmosphere. But this isn’t the whole picture.

Our data shows any potential increase in photosynthesis resulting in greener forest canopies has not translated to greater carbon storage in stems and branches.

The reason may be that tree growth can be limited by water, nutrients and heat. Our work suggest that warmer and drier conditions have limited tree growth even as CO₂ concentration has increased.

In a separate study, scientists artificially increased CO₂ and found the extra carbon taken up by leaves wasn’t being stored as extra woody growth. Rather, it was quickly released through roots and soil microbes.

What about other forest carbon stocks?

It will be challenging to find out whether these forests as a whole (including wood, roots, leaves and soils) have declined in carbon sink capacity.

The use of a specialised research tool known as eddy covariance towers could help, as these measure overall CO₂ movement into and out of ecosystems.

As of yet, only 15 years of this kind of data from three tropical Australian sites is available, which currently limits our ability to describe the fuller impact of climate change.

In any case, we know carbon stored in forest canopies and soils is often broken down and released back to the atmosphere faster than carbon in woody biomass.

So while Australia’s tropical rainforest carbon stores remain large, they may be less secure and reliable than in decades past.

Long term datasets are vital

When people visit Australia’s tropical rainforests, they can see intact stretches of biodiverse forest and large, carbon-rich trees. It’s hard to directly see the changes we have detected – for now, they’re only visible in the data.

Without high-quality long-term datasets, this signal would have been almost impossible to detect. Unfortunately, persistent funding shortages for long-term ecological monitoring threaten the continuity of these hugely valuable datasets.

Australia has the potential to assume a globally leading role in tropical ecosystem science. In light of state and national biodiversity and emission reduction commitments, Australian governments should support continued monitoring of vital ecological research sites.

Tropical forests may not be saviours

The fact that woody biomass in Australia’s tropical rainforests is now a net source of carbon has major implications.

These findings challenge our future reliance on forests as natural absorbers of extra atmospheric carbon.

We don’t know yet whether all tropical forests will respond similarly. Evidence on carbon sink capacity is mixed. Rainforests in South America are showing a decline while African rainforests are generally not.

Overall, the world’s tropical forests remain very significant stores of carbon and biodiversity. Their protection remains essential despite the climate risks they face.

Hannah Jayne Carle, Postdoctoral Researcher in Tropical Forest Ecology, Hawkesbury Institute for the Environment, WSU, Australian National University; Adrienne Nicotra, Professor of Ecology and Evolution, Research School of Biology, the Australian National University, Australian National University; David Bauman, Research Scientist in Plant Ecology, Institut de recherche pour le développement (IRD); Michael N Evans, Professor in Earths Systems Science, University of Maryland, and Patrick Meir, Honorary Professor of Forest Ecosystems, Australian National University; University of Edinburgh

This article is republished from The Conversation under a Creative Commons license. Read the original article.