Reuters: World on brink of environmental tipping points, UN says

[OKIsItJustMe]

World on brink of environmental tipping points, UN says

By David Stanway
October 25, 2023 5:03 AM EDT

SINGAPORE, Oct 25 (Reuters) - The world is heading towards a series of environmental "tipping points" that could cause irreversible damage to water supplies and other life-sustaining systems, the research arm of the United Nations warned on Wednesday.

Climate change and the overuse of resources have put the world on the brink of six interconnected tipping points that "could trigger abrupt changes in our life-sustaining systems and shake the foundation of societies," the UN University's Institute for Environment and Human Security (UNU-EHS) said.

"Once these thresholds are passed, the system fails to function as it normally would, and you get new risks cascading out, and these new risks can transfer to other systems," said UNU-EHS researcher Jack O'Connor, lead author of the report.

"We should be expecting these things to happen because in certain areas they are happening already."

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[jfz9580m]

1. "the overuse of resources "

Yup..we are an expensive species...

[cstanleytech]

2. As long as we have enough plankton producing the oxygen we need to breathe just about everything else is

survivable for our species.

[OKIsItJustMe]

3. Wired: This Heat Is Shaking the Very Foundation of the Ocean Food Web

MATT SIMON | SCIENCE | AUG 2, 2023 7:00 AM

This Heat Is Shaking the Very Foundation of the Ocean Food Web

Yes, save the corals. But warming seas also imperil innumerable plankton, which power the oceanic ecosystem.

…

Heat on its own isn’t the only concern. When oceans warm, a few things happen physically and chemically to the surface waters that these organisms call home. The warmer seawater gets, the less oxygen it can hold. As the planet rapidly warms, scientists have found that ocean oxygen levels have been steadily dropping, in some cases precipitously: The loss is up to 40 percent in tropical regions. That, of course, deprives organisms of the oxygen they need to survive.

Secondly, the warmer water gets, the less dense it becomes. At the surface, you end up with a band of hot water, with cooler waters in the depths, a layering known as stratification. “If you've ever gone swimming in a lake in the summer, if you're at the surface, it's nice and warm, and then you dive down and it gets cold pretty fast,” says Michael Behrenfeld, an ocean ecologist at Oregon State University. “That's the stratification layer that you're going through.”

In the ocean, this warm water acts like a cap that interrupts critical ecological processes. Normally, nutrients well up from the depths, providing food for the phytoplankton floating at the surface. Stratification prevents that. In addition, winds typically blow across the surface and mix that water down deeper, also bringing up nutrients. But with stratification, the contrast between the surface layer of warm water and the underlying cold water is so strong that it’s very difficult for wind energy to mix the two.

Together, all of these mean that phytoplankton in a warmer ocean are deprived of the nutrients they need. In response, they produce fewer of the pigments they use to turn sunlight into energy. “Phytoplankton will decrease their photosynthetic pigments because they're becoming more nutrient-stressed,” says Behrenfeld. “They don't need to harvest as much light because they don't have enough nutrients to do as much photosynthesis as they did before.” (Behrenfeld can actually see transformation in satellite imagery.)

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[cstanleytech]

5. Yes, I know and thats why I said "if" because ""if" the oxygen supply collapses we are screwed.

[OKIsItJustMe]

6. I thought you did, but I like to provide background for people who don't

[redqueen]

4. Earth Overshoot Day was August 2. nt

[OKIsItJustMe]

7. New UN University Report Warns about Risk Tipping Points with Irreversible Impacts on People and Planet

Press Release
New UN University Report Warns about Risk Tipping Points with Irreversible Impacts on People and Planet

Drastic changes are approaching if risks to our fundamental socioecological systems are not addressed.

Date Published 25 Oct 2023

A United Nations University report released today finds that drastic changes are approaching if risks to our fundamental socioecological systems are not addressed.

The Interconnected Disaster Risks Report 2023 published by the United Nations University – Institute for Environment and Human Security (UNU-EHS) warns of six risk tipping points ahead of us:

• Accelerating extinctions
• Groundwater depletion
• Mountain glaciers melting
• Space debris
• Unbearable heat
• Uninsurable future

Systems are all around us and closely connected to us: ecosystems, food systems, water systems and more. When they deteriorate, it is typically not a simple and predictable process. Rather, instability slowly builds until suddenly a tipping point is reached and the system changes fundamentally or even collapses, with potentially catastrophic impacts.

A risk tipping point is defined in the report as the moment at which a given socioecological system is no longer able to buffer risks and provide its expected functions, after which the risk of catastrophic impacts to these systems increases substantially. These diverse cases illustrate that risk tipping points extend beyond the single domains of climate, ecosystems, society or technology. Instead, they are inherently interconnected, and they are also closely linked to human activities and livelihoods.

…

Nothing to see here. Move along…