Showing all posts tagged: environment

Tropical cyclones may return to Sydney coastal region

24 November 2022

For about thirty years, until the mid-seventies, tropical cyclones were relatively regular weather events in the Sydney region, but now meteorologists are concerned they may return. But climate change is not behind their possible re-emergence, rather changes in the Interdecadal Pacific Oscillation (IPO):

The inordinate frequency of cyclones from the 40s to the 70s and the disappearance in recent decades is not random variability. A 2020 report in the Journal of Southern Hemisphere Earth Systems links NSW cyclone activity with changes in the Interdecadal Pacific Oscillation (IPO). The current state of the IPO and other cyclone influences has rapidly shifted in the past three years to resemble the 1950s. Meaning, the current phase of the Pacific is conducive to tropical cyclones impacting NSW.

While more often see in northern regions of Australia, tropical cyclones haven’t reached Sydney in decades, but they have impacted some parts of NSW, bringing flooding and storm damage with them.


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The Climate Book by environmental activist Greta Thunberg

3 November 2022

The Climate Book, by Greta Thunberg, book cover

The Climate Book, written by Swedish environmental activist Greta Thunberg, and published this month by Penguin Books, sets out the facts about climate change, and outlines solutions for dealing with it. As Thunberg says, we need to act now, if we want to make a difference.

In The Climate Book, Greta Thunberg has gathered the wisdom of over one hundred experts – geophysicists, oceanographers and meteorologists; engineers, economists and mathematicians; historians, philosophers and indigenous leaders – to equip us all with the knowledge we need to combat climate disaster. Alongside them, she shares her own stories of demonstrating and uncovering greenwashing around the world, revealing how much we have been kept in the dark. This is one of our biggest challenges, she shows, but also our greatest source of hope. Once we are given the full picture, how can we not act? And if a schoolchild’s strike could ignite a global protest, what could we do collectively if we tried?


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Ocean heat absorption highest in waters around Antarctica

12 September 2022

While all the world’s oceans are absorbing some degree of heat, and somewhat moderating the rate of global warming, the Southern Ocean, being the waters that generally surround Antarctica, is soaking up the most excess warmth.

Ocean warming buffers the worst impacts of climate change, but it’s not without cost. Sea levels are rising because heat causes water to expand and ice to melt. Marine ecosystems are experiencing unprecedented heat stress, and the frequency and intensity of extreme weather events is changing. Yet, we still don’t know enough about exactly when, where and how ocean warming occurs.

Even if carbon dioxide emissions ceased overnight, it could thousands of years for heat trapped in the oceans to be released again.



A spring of Sam (Southern Annular Mode) and La Nina summer?

5 September 2022

Rainy evening, photo by John Lampard

Image courtesy of disassociated.

While there’s a slim chance regions of Australia may yet be spared a third consecutive wet, rainy, La Niña weather event this summer, the outlook for spring is not so promising.

The Bureau of Meteorology advised last week parts of eastern Australian can expect higher than usual rainfalls, thanks to another meteorological phenomenon, a positive Southern Annular Mode, or Sam, for short:

Further, Dr Bettio said a positive Southern Annular Mode (SAM) is also likely, which pushes weather systems south, bringing wetter easterly winds to NSW and fewer cold fronts to western Tasmania. Dr Bettio said parts of Western Australia and western Tasmania are likely to experience below average rainfall this spring. Almost all of Australia is likely to experience warmer than average nights, while cooler days are likely for large parts of the mainland except the tropical north.


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Greenland ice cap melt inevitable sea levels may rise 27cm

31 August 2022

We’re passed the time for warnings… a significant increase in sea levels is unavoidable, with the melting of the Greenland ice cap expected to add twenty-seven centimetres to global ocean tidemarks. It could be a whole lot more if (or when) other ice masses melt:

Major sea-level rise from the melting of the Greenland ice cap is now inevitable, scientists have found, even if the fossil fuel burning that is driving the climate crisis were to end overnight. The research shows the global heating to date will cause an absolute minimum sea-level rise of 27cm (10.6in) from Greenland alone as 110tn tonnes of ice melt. With continued carbon emissions, the melting of other ice caps and thermal expansion of the ocean, a multi-metre sea-level rise appears likely.


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Australia on alert for a third La Nina event this summer

18 August 2022

Another wet summer may be on the cards for parts of Australia, after the Bureau of Meteorology moved the ENSO Outlook to a La Niña alert status.

This status change follows a renewal of cooling in the tropical Pacific Ocean towards La Niña thresholds over recent weeks, as well as the persistence of the Southern Oscillation Index (SOI) at La Niña levels and strengthened trade winds at La Niña levels. Climate models indicate further cooling is likely, with four of seven models suggesting La Ni Niña a could return by early-to-mid southern hemisphere spring.

If another La Niña eventuates this summer, it will be the third in a row.


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Climate change aggravates the spread of infectious diseases

15 August 2022

In the same week a reminder that climate change exasperates the emergence and spread of infectious diseases is issued, news that polio has been detected in New York sewage, and an instance of a virus, Langya henipavirus, spreading from animals to humans in China, are reported. This on top, of course, of COVID, and the more recent Monkeypox outbreak.

The continual release of greenhouse gases (GHGs) is escalating several climatic risks, which, in turn, worsen human pathogenic illnesses. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, which amply demonstrated the social upheaval driven by infectious diseases, offers alarming hints to the possible outcomes of impending health crises caused by climate change.


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The first year in the life of a mango tree time lapse video

25 July 2022

Incredible time lapse video footage of the growth of a mango tree, from being planted as a seed, to a year later, from the people at Boxlapse.

I once lived in house that had a mature mango tree in the back yard. It was sizeable, three metres, maybe a little higher, planted on the fence line. Now I know what I missed earlier on.


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Forests now cover two percent of Iceland thanks to replanting

22 July 2022

In the distant past, forests and trees covered large parts of Iceland, about forty percent of the country. But when permanent settlers arrived over a thousand years ago, much of this growth was cleared to make way for agriculture and grazing, and firewood. Efforts to replant trees since the 1990s though have seen forest areas return to two percent of the country today.

That number may not seem like much, but since 1990, the surface area covered by forest or shrubs in Iceland has increased more than six times over – from 7,000 hectares to 45,000. In 20 years, the number is expected to be 2.6%.

Every little bit helps. It’s a hopeful reminder that it’s not too late to take steps of any sort to deal with climate change.


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Don’t plant trees to combat climate change plant mini-forests

15 July 2022

Urban mini forest, photo by uniquedesign52

Image courtesy of 二 盧/uniquedesign52.

Planting trees is one way of mitigating the impact of climate change, but planting mini-forests is a more effective alternative, says American nature and conservation writer Hannah Lewis.

Mini-forests are more likely to nurture ecosystems, rather than single trees planted here and there, and, as a result, live longer. And better still, mini-forests can be established anywhere, even in densely populated urban areas, where there’s even a few spare square metres of land available.

A mini-forest is a small ecologically robust forest that can be planted by communities in parks and cities, in schoolyards and churchyards, and beside busy roads. It’s flipped traditional landscaping on its head. You get more biodiversity and a different appearance. It’s a dense band of multi-layer trees as opposed to the elegant but less ecologically useful line of single species down the side of the street.

Lewis’ call is based on the work of late Japanese botanist Akira Miyawaki, who advocated the planting of small forests with native species, as a way of fostering the emergence of ecosystems.


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