Climate Change

[Dr Sardonicus]

Study: Many birds nesting, laying eggs earlier in Chicago

CHICAGO (AP) - Many species of birds are nesting and laying eggs nearly a month earlier than they did 100 years ago in the Chicago area and researchers believe climate change is behind it.

Those were among the findings in a new study published in the Journal of Animal Ecology. Researchers compared recent observations with century-old eggs preserved in museum collections.

"We learned that birds in the Chicago region, at least some species, are nesting as much as 25 days earlier now than they were back in the early 1900s and late 1800s," said John Bates, curator of birds at Chicago's Field Museum and the study's lead author. "This study was designed to basically look at whether or not bird species in the northeastern part of Illinois were changing their egg-laying dates over time."

The museum has 50,000 to 60,000 eggs in its collection dating from the 1870s to the 1920s. The collection includes information about the eggs. The Field's collection, like most, drops off after the 1920s, when egg-collecting went out of fashion for hobbyists and scientists.

The findings were consistent with other things going on in the environment because of climate change, Bates said.

"Insect numbers have been shown to be declining, too, although again, it's hard to have good data on what each species of insect is doing," he said. "And insects, in turn, are responding to plant leaf out, and so that's also something that's moving forward in time."

Besides serving as a warning about climate change, the study highlights the importance of museums' egg collections, which are often underutilized.

"There are 5 million eggs out there in collections worldwide, and yet, there are very few publications using museum collections of eggs," Bates said. "They're a treasure trove of data about the past, and they can help us answer important questions about our world today."

[Dr Sardonicus]

The journal Science has published a paper, Assessing ExxonMobil's global warming projections, which indicates their scientists had done a really good job predicting how the climate would change in the years to come.

In those years, the company was officially denigrating the science.

This brings to mind what happened with Johns-Manville lo, these many years ago...

[Dr Sardonicus]

Antarctic sea-ice at 'mind-blowing' low alarms experts

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The ice that floats on the Antarctic Ocean's surface now measures less than 17 million sq km - that is 1.5 million sq km of sea-ice less than the September average, and well below previous winter record lows.
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I've seen the early-summer low sea-ice described as a "five-sigma event" or a "six sigma event" depending on whose article it was. Since these were in regard to averages over a few decades, I'm not sure how significant that is. But it's a precipitous drop in any case.

Last year, the sea ice was also very low: Climate change: Thousands of penguins die in Antarctic ice breakup

A catastrophic die-off of emperor penguin chicks has been observed in the Antarctic, with up to 10,000 young birds estimated to have been killed.The sea-ice underneath the chicks melted and broke apart before they could develop the waterproof feathers needed to swim in the ocean.

The birds most likely drowned or froze to death.

The event, in late 2022, occurred in the west of the continent in an area fronting on to the Bellingshausen Sea.
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Dr Fretwell and colleagues report the die-off in the journal Communications Earth & Environment.

The scientists tracked five colonies in the Bellingshausen Sea sector - at Rothschild Island, Verdi Inlet, Smyley Island, Bryan Peninsula and Pfrogner Point.

Using the EU's Sentinel-2 satellites, they were able to observe the penguins' activity from the excrement, or guano, they left on the white sea-ice.

This brown staining is visible even from space.

Adult birds jump out on to the sea-ice around March as the Southern Hemisphere winter approaches. They court, copulate, lay eggs, brood those eggs, and then feed their nestlings through the following months until it's time for the young to make their own way in the world.

This normally occurs around December/January time, when the new birds head out into the ocean.

But the research team watched as sea-ice under emperor rookeries fragmented in November, before thousands of chicks had had time to fledge the slick feathers needed for swimming.

Four of the colonies suffered total breeding failure as a result. Only the most northerly site, at Rothschild Island, had some success.

Antarctic summer sea-ice has been on a sharp downturn since 2016, with the total area of frozen water around the continent diminishing to new record lows.

The two absolute lowest years have occurred in the past two summer seasons, in 2021/22 and in 2022/23, when the Bellingshausen was almost completely devoid of ice cover.
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