Cael et al. used 20 years of satellite data to measure changes in the color of the oceans. They are getting greener as the result of more phytoplankton (microscopic plants and bacteria that live in the upper layer of the ocean). Phytoplankton form the base of – and sustain – the aquatic food web.
Global climate-change trends detected in indicators of ocean ecology
https://www.nature.com/articles/s41586-023-06321-z
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Zhu et al. also used long-term satellite data to study the increase in global vegetation. Only 4% showed browning – decreasing LAI (leaf area index). Their attribution work on the causes of global greening found the following percentages:
Increased CO2 70% N deposition 9 Warming 8 Land cover changes 4
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This paper has been parroted by more than 20 sources. Most of those simply repeat the same clickbait title.
That paper presents no conclusion other than the one stated in their first observation.
They discuss method, findings and conclusion which is, put simply: “It’s getting greener.”
The “not good news” is a click bait phrase.
If you are an arid climate plant or animal and your primary sustainment relies on drier environments to keep competition down or to reduce fungal or other parasitic load, getting greener (wetter) could be bad news.
They postulate that CO2, moisture loading and temperature are possible inputs to the greening. I can almost see them sitting there in a contemplative head’s scratching state saying “…and we don’t know much else…”
There is no conclusion pointing to anything specific or general which is good or bad news.
From the discussion section:
"Although it is possible to subdivide the 20-year study period into 10 or 5 years and study short-term trends, this yields different results depending on how the period has been divided. The calculation method itself is skewed by the starting year: the result will be higher than real life if the starting year had relatively less vegetation. This could be the case if the period coincided with a particularly dry phase in the El Niño cycle. It is also possible that the observed 20-year trend is an anomalous phenomenon within much longer climatic cycles. As satellite data only cover the period from the 1980s, alternative datasets indicating vegetation changes would be needed to indicate whether these recent trends are part of such longer-term cycles or the consequence of more recent anthropogenic climate change. However, this result can form part of the basis of our interpretation of greening and browning trends in natural systems on the Pacific slope for which long-term study is required to monitor and confirm."
"Exploring causality for this phenomenon is problematic since, as one moves south, the greening strip ascends, which would seem counterintuitive. That is, plant productivity would be expected to decline as temperature declines with increasing altitude and latitude, temperature being a primary limiting factor in photosynthesis.
The increase in global CO2 contributes to the globally observed greening phenomenon and could account for greening inside and outside of the defined strip, but this cannot explain the shorter-term regionally determined fluctuations in EVI.
We must, therefore, look to moisture availability, the third driver in vegetation growth. Figure 11 and Table 3 show the correlations between the 20-year trend in EVI within the greening strip and sea surface temperature (SST), precipitation and global CO22 concentrations over the same time period.
The paper presents a great observation and a nice use of satellite imagery. It will be a good support for other findings in data.
There were no conclusions offered except that, “It’s greener now than most years in the past 20 years”.
That is for good reason as the world is more complicated than people often expect.
The argument climate change apologists like to make is that higher CO2 increases crop yields. This means global warming is a good thing so let’s keep burning coal. Oddly, however, they always leave out (as in the OP) something long known to plant biologists, increasing CO2 reduces protein and mineral content in plant tissue. That means you get more crops of poorer nutritive quality. It is estimated that rising CO2 levels will have a net negative effect on global nutrition by midcentury. https://www.thelancet.com/journals/lanplh/article/PIIS2542-5196(19)30108-1/fulltext
Crops with less protein means that the pest insects will have to eat more plant material to be satiated. Rising temperatures also means that these pests have shorter development times and so will undergo more generations during the year. That’s why many predict an increase in pest pressure on crops. And while CO2 stimulates crop growth it shouldn’t be ignored that it also stimulates weeds. Hence predictions that global warming will significantly increase the use of chemical pesticides and herbicides.
Rising CO2 may be greening the globe, but the impact on agriculture is uncertain and will be region dependent. It’s complicated.
The global greening continues despite increased drought stress since 2000
https://www.sciencedirect.com/science/article/pii/S2351989423004262
Highlights
The global greening is an indisputable fact.
The rate of global greening increased slightly.
The drought has only slowed the global greening, but not caused the global browning.
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Less than 4% of dryland areas are projected to desertify despite increased aridity under climate change
Zhang et al.
https://www.nature.com/articles/s43247-024-01463-y
Future projections show continued increases in aridity due to climate change, suggesting that drylands will expand. In contrast, satellite observations indicate an increase in vegetation productivity…
Here we used a data driven approach to show that increasing aridity in drylands won’t lead to a general loss of vegetation productivity…
We found a broad boost to dryland vegetation productivity due to the carbon dioxide (CO2) fertilization effect that is negated by climate changes in at most 4% of global drylands to produce desertification.
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That does NOT mean the vegetation will be desirable.
Here in Central Texas, rising CO2 concentration has benefitted poison ivy. This was noted back in the 1990s.
In general, every living thing needs Nutrients Energy Water and the “right environmental” Temperature.
NEWT.
Which ever of those is in the least supply is the rate limiting resource.
CO2 is a “Nutrient”. As CO2 rises, it becomes “less” rate limiting.
For most plants, water turgor pressure keeps stomata open, for gas exchange: CO2 into the plant.
CO2 diffuses along its concentration gradient into the plant. Higher atmospheric CO2 concentration means CO2 diffuses more readily into the plant, even under “dry” conditions.
At any rate, which ever resource is in “least” supply, becomes the growth limiting step.
In temperate climates, this changes with season (winter vs spring/summer for temperature; spring rain vs dry summer for Water.; etc)
FWIW 
ralph
NPK is added to soil so that these nutrients are not the rate limiting resource.
Zinc for pecan trees, etc.
Irrigation so that water is not the limiting resource.
Bats use highway bridges cause that gives them the “right environmental T”, close to N E n W.
Homeless live where they live cause they are able to access NEWT there.
For me, to not have deserts expanding is a good thing. Back in '07 Natalie Mahowald modeled future desertification. She wrote:
If I assume no carbon dioxide fertilization, the mean of the model predictions is that desert areas expand from the 1880s to the 2080s, due to increased aridity. If I allow for carbon dioxide fertilization, the desert areas become smaller.
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2007GL030472
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Global greening means the biosphere is absorbing carbon from the atmosphere and acts as a carbon sink.
New analysis shows that there was a large and suprising drop in the carbon sink in 2023. It looks like it’s only a preprint on the arXiv (the standard place for preprints), so they could have a sign error, but if the analysis holds true it’s a puzzle and a concern. Expect more to come.
The abstract says:
This [the analysis] implies an unprecedented weakening of land and ocean sinks, and raises the question of where and why this reduction happened.
and ends with
indicating that record warming in 2023 had a strong negative impact on the capacity of terrestrial ecosystems to mitigate climate change.
“In 2023, the CO2 growth rate was 3.37 +/- 0.11 ppm at Mauna Loa, 86% above the previous year, and hitting a record high since observations began in 1958, while global fossil fuel CO2 emissions only increased by 0.6 +/- 0.5%.”
During the pandemic year, carbon dioxide emissions actually declined by a bit over 5% and yet the level in the atmosphere increased, so there is only a loose connection.
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The connection is the carbon sink. Carbon emissions minus carbon sink = atmospheric carbon growth.
That is true by definition. My point was that the changes in the variables show only a loose correlation.
Chg in human Chg in CO2
emissions concentration
2019 + 0.5% + 0.7%
2020 - 5.4% + 0.6%
2021 + 5.1% + 0.5%
2022 + 0.9% + 0.5%
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The percentage of carbon dioxide that stays in the air is called the airborne fraction. Bennedsen et al. recently confirmed there is no long-term trend in the airborne fraction.
“Testing the hypothesis of the presence of a trend in the airborne fraction (AF), defined as the fraction of CO2 emissions remaining in the atmosphere, has attracted much attention, with the overall consensus that there is no statistical evidence for a trend in the data…A re-examination of the data using a variety of statistical tests finds no evidence of a trend on the whole sample and some evidence of a positive trend when a break in the level of the AF is accounted for.”
https://www.nature.com/articles/s41586-023-05871-6
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This is why the new analysis showing a drop in the carbon sink in 2023 is getting attention. It’s surprising.
I see three possibilities
The combination of extreme record warmth and a rare carbon sink fluctuation in the same year could be a coincidence. Or it could be related. There’s no way to tell so far. Stay tuned.
From earlier…
How well do we really know the accuracy of the Carbon emissions term? If there were more carbon or carbon-equivalent emissions than what was officially reported, that might throw off the carbon sink estimate?
Some reasons why there might be more carbon emissions than what we think:
_ Pete
The IPCC AR6 2022 Summary for Policymakers says
Global net anthropogenic GHG emissions were 59 ± 6.6 GtCO2-eq (7,8) in 2019,
Footnote 8 says
- In this SPM, uncertainty in historic GHG emissions is reported using 90% uncertainty intervals
Using direct measurements of CO2 exchange, or fluxes, between the air and sea, the scientists found the ocean around Antarctica absorbs 25% more CO2 than previous indirect estimates based on shipboard data have suggested. The Southern Ocean plays a major role in absorbing CO2…
The results – published in the journal Science Advances - show the summer Southern Ocean is likely to be a strong CO2 sink, challenging the much weaker estimates based on float data and model simulations, which the authors say “substantially underestimate” the observed CO2 uptake…
Lack of winter data is a general problem with ships because of the difficulty accessing the region at that time, which the floats partially address. Acknowledging that their cruise data only covers some parts of the Southern Ocean in summer, the authors say continued efforts towards high-quality observations are essential to improve estimates of air-sea CO2 fluxes.
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