A science presenter, writer, speaker & former TV host; author of The Skeptic's Handbook (over 200,000 copies distributed & available in 15 languages).



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Stop That Now! Climate change helps aggressive mangrove forests build bigger tropical islands

The oceans were supposed to be swallowing up the islands

Climate change has unleashed rampant growth in mangrove forests. The trees are capturing coral detritus in large sand drifts, and locking it into whole new ecosystems that expand 5 to 6 meters a year. It’s just remarkable — some islands have grown by several kilometers since 1928.

The Howick Group of islands is north of Cairns Australia. Three scientific expeditions mapped out them out in 1928 and in 1974, and again in 2021, and lo, they have grown, especially in the last four decades. That makes them like most of the 709 islands of the Pacific and Indian oceans that were studied a few years ago. Satellites showed that 89% of those islands had grown.

It turns out warmer more carbon rich world makes mangroves happy. Who could have seen that coming, apart from every biologist on Earth?

From the commentary in the video below:

“We’ve seen some really dramatic changes. Some of the things that we’ve seen are advancing fronts of forests. Forests that were mapped to small patches on the windward part of the reef flat are now occupying a much larger section of […]

In a warming world we may get overun by cheap soy and corn

New research shows that the impending climate disaster puts the world in danger of growing too much corn and soy. People won’t know what starving is!

H/t to CO2Science

Qiao et al discovered that when temperatures are raised by a “catastrophic” 2 degrees C, and CO2 is raised to 700 unthinkable ppm corn (aka maize) increases its yield by a remarkable 25%. When hit by both high temperatures and extra CO2, soy bean yield increased even more — by 31%.

Presumably this means crop prices will fall and corn and soy may take over your garden. (So make sure you put in a solar panel to control those new weeds!)

Rumour that nutrient densities will fall — proved to be false. Increased temperature raised the oil content of both crops. And the combo of warmer weather plus CO2 increased most of the nutrients as well. Both crops had more phosphorus, potassium, iron, and zinc. There was a statistically small decrease in calcium in maize, so small it may not be there. The only mineral that definitely declined was manganese in soybeans, and as far as humans go, there is apparently no one on Earth who has a clinical manganese deficiency […]

Burn oil so we can eat more chocolate

The fake scare of the season — “climate change is impacting chocolate production”.

Chocolate is produced from the beans that grow on cocoa trees. These plants can only grow in a fairly narrow range of conditions, which makes them vulnerable to changes in the environment.

Unfortunately, climate change is threatening some of these key growing regions. According to the IPCC, rising temperatures and a relative reduction in rainfall could make areas like West Africa less suitable for cocoa production in the future. Changes to the climate are also pushing cocoa-growing regions to higher altitudes in some parts of the world, which can make some crops unsustainable.

We can see just how hard cocoa crops have been hit by record heat and 500 billion tons of carbon.

Global Cocoa production

Since 1989 humans have put out more than 50% of all anthropogenic CO2 emissions since homo sapiens went sapien. There is an undeniable trend here.

Happy Easter to everyone.

h/t Dave B

9.6 out of 10 based on 61 ratings

If world warmed — crops could grow another 1,200 km further North

Climate change might bring more food as it expands into the arctic. In a big surprise, scientists found that agriculture works best in places without much snow and ice.

Burn oil and feed the world

Only a third of the giant northern boreal forest is able to be cropped at the moment. With any luck, serious global warming will set in, allowing us to raise the edge of the zone of arable land and feed millions more hungry people.

Obviously , we need to spend billions to stop this.

Though Canadians and Russians may disagree (especially if they thought CO2 actually mattered, but who does?).

Given CO2’s mixed performance in the last hundred years, I predict disappointment…

9.3 out of 10 based on 60 ratings […]

Eucalyptus trees cope fine with extreme heatwaves, defy climate models, survive 50C temps

What happens to a poor tree when you withhold rain for a whole month, then hit it with four days in a row of 43C temperatures? It was so hot, some of the leaves on these trees got close to 49-50 °C.

In at least one gum species in Australia, the answer is “not much”. They suck up lots of water from their deep roots and sweat it out til the heatwave passes. The trees become evaporative coolers “siphoning up” water. They cope so well, that not only did the trees not die, but their trunk and height growth were unaffected. Indeed, only about 1% of the leaf area even exhibited browning.

Whole tree chambers in Richmond, New South Wales, Australia. Twelve 9-m-tall chambers in a field setting (a) enclose the canopies of individual Eucalyptus parramattensis trees rooted in soil (b). Two heatwave chambers can be seen on the left of the infrared image, along with several control chambers (c; temperature in °C).

But with global warming running at a heady 0.13C per decade, you might wonder how many years will it take for the trees to adapt?

From the paper — “one day”:

The gums rapidly […]

Burn more oil and feed the world

Climate change causes … more crops.

Climate change threatens our food supply, our grain harvests. It causes wars, droughts, sometimes floods, shorter growing seasons. And we all know Climate change is here. We can see it out the window. Plus 2017 is one of the three hottest years ever.

Somehow all these bad events happened at once and added up to the world’s largest cereal crop ever.

It’s doom gloom and fume all the way down:

How a warming world is threatening supplies — The Guardian

Climate Change May Reduce Some U.S. Grain Harvests by Half –– Bloomberg

Wheat, one of the world’s most important crops, is being threatened by climate change —Washington Post Record cereal production leading to record end-season inventories in 2017/18

“World wheat inventories are currently pegged at an all-time high despite a downward revision since October. Global stocks of rice and coarse grains are also set to reach record levels. The increase in wheat and rice stocks largely reflects an anticipated accumulation of inventories in China, whereas for coarse grains, the expansion reflects higher end-of-season maize stocks in South America and the United States.” […]

Record hottest year means record bumper wheat crop, opposite of crop models

Last year there were warnings from crop modelers in Nature that heat kills wheat and yields were going to fall in the “near future”, if temperatures rose. In fact global warming was “already slowing wheat gains”. What followed was a record El Nino, and 2015 was the hottest ever year, with 2016 vying to beat it. But instead of wheat doom, this month the USDA forecasts a record yield of wheat with bumper crops globally. Wheat output has grown in Australia, the US, Russia, Ukraine, everywhere pretty much, except the EU where it has been too rainy. Where are the mea culpas? h/t to the GWPF

Jan 2015, published in Nature. “Global Wheat Yield May Drop as Temperatures Rise”

“… researchers are now letting farmers know that the world’s wheat yields are excepted decline in the near future, with the world standing to lose six percent of its wheat crop for every degree Celsius that the annual global temperature increases.

“The simulations with the multi-crop models showed that warming is already slowing yield gains, despite observed yield increases in the past, at a majority of wheat-growing locations across the globe,” researcher Senthold Asseng, at the University […]

18 million square kilometers more greenery due to “carbon pollution” that the Greens hate

What kind of pollution do you want to feed your plants? The carbon kind.

Yet again, a satellite study of leaf area shows that the world is greener than it was in 1982. There are more plants mostly thanks to CO2 aerial fertilization. The biggest benefits from CO2 are in the warm tropics. The extra greenery in colder areas was due to that other disaster called “global warming”. About a tenth of the greening had nothing to do with either carbon pollution or extra warmth and was apparently thanks to nitrogen from man-made fertilizers.

Obviously we need a $10 billion dollar program to stop this immediately.

Click to enlarge.

Humans are Greening planet Earth — ABC

The most comprehensive modelling of remote sensing data so far shows the area on Earth covered by plants in this time has increased by 18 million square kilometres — about 2.5 times the size of the Australian continent — largely due to the fertilising effect of carbon dioxide (CO2).

“[The greening] has the ability to fundamentally change the cycling of water and carbon in the climate system,” said Dr Zaichun Zhu, from Peking University in China and lead author […]

Burn oil, feed the world, grow plants, save forests, get richer, live longer. Why we urgently need to raise CO2.

It’s time to stop pussy footing around. We need higher levels of CO2. It is morally and ethically irresponsible to be silent while millions starve, biodiversity is under threat, and people are dying from cold weather.

Carbon dioxide increases crops, forest and plant life by 14% and is worth $140 billion, just in agricultural production. Thanks to CO2, forests have been protected because farms are more efficient in a higher CO2 world.

Countries that don’t do their part in producing enough carbon dioxide emissions need to lift their game. Coal use should be favoured over nuclear, hydro, wind and solar. Countries like France are free-riding on the nations like China, the US, and Australia — which are helping to green the world and feed the starving.

Indur Goklany has put together a comprehensive report on the benefits of CO2 for the GWPF.

The advantage of higher CO2 for all C3 crop plants is spectacular. That’s rice, wheat, barley, rye, cotton, sugar beet, spinach, and potato. C4 plants evolved in the last 30 million years to be good at dealing with low CO2 atmospheric concentration (corn, sugarcane, cabbage, broccoli, sedge, daisy.) Most plants are C3.

Figure 1: Carbon dioxide fertilization […]

Welcome to the CO2 disaster — 4 billion tons more plants, more greenery

During the recent warmest decades on record, Earth suffered under the highest CO2 levels of the last 800,000 years. Life responded to this devastating situation by — flourishing. There are now some 4 billion tons more living matter on the planet than there was in 1993. What a calamity. (And what a lot of carbon credits.)

It has, naturally, got nothing to do with warmth and aerial fertilizer. The researchers tell us it due to that force of nature known as “good luck”. Remember, human CO2 emissions were pollution that was going to afflict life on Earth. After twenty years of predicting the loss of forests and species, it turned out that biology bloomed instead. Notch up another model “success”. The press release headline: Good luck reverses global forest loss. (What else would we expect from UNSW?)

To those who know basic biology — and that almost half the dry weight of plants is carbon, sucked straight out of the air — this is not so much good luck as one entirely foreseeable and foreseen consequence of rising CO2. Acquiring carbon is often a plant’s hardest task. When the sun comes up, a cornfield begins sucking, and by lunch time […]