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There are 9 comments on Humans Are Officially Greening the Earth. Is That a Good Thing?

  1. I think the authors have discovered more about the faulty assumptions in their own models than they have about the actual dynamics of human land use and environmental change in the past two decades. I am not familiar with India’s recent land use history, but having worked on agriculture and forestry in China over the past several decades I find these findings unsurprising.
    And if one looks at environmental impacts more holistically instead of focusing narrowly on GHG emissions, it is clear that a forest delivers a whole set of other environmental services — water regulation, biodiversity, soil conservation, etc, etc — that intensified cropping does not.
    Intensive industrial agriculture and forestry are both associated with monocultures, and both deliver poorly when it comes to the larger package of ecosystem services. (Although fast-growing plantation forests may in some circumstances store more carbon more quickly than natural regrowth on the same site.) I wonder if the authors can find a way to distinguish patterns of leaf cover so that they can make comparisons between monoculture and diverse tree and crop systems at different scales. Combined with robust ground-truthing, (and ideally a larger set of environmental indicators) such a refinement could play an important role in informing future land use policies.

  2. »Instead, carbon absorbed by crops is quickly released back into the atmosphere»

    I don’t get it. How does that happen? How does crop release its carbon? How much of it? How quickly does this happen?

  3. Author assumptions doesn’t matter.In this very article emmission of corbon and it’s current situation might be correct.But the solution they are saying is because of agriculture and crop rotation will be hazards for water crisis .
    The only way to emmission of corbon is planting tree because they don’t need regular irrigation.

  4. So China and India have turned barren land, desrts, into forests and farmlands and created a global increase in green land by 20%?
    Sorry I dont buy that. Sounds like a desperate attempt to downplay a positive effect of CO2 fertilisation of the Atmosphere. Commercial plant growers raise CO2 to 1000 ppm at least in their greenhouses to get a better yield. Of course that effect is real, it is just petty and stupid to claim the opposite.

    1. Some plants can adapt to increases in CO2 better than others. Outside of an enclosed greenhouse, there will be competition for space, resulting in a biodiversity change. The faster growth will also leech nutrients faster from the soil. The hot air and increase in evapotranspiration will mean plants will not have the water needed. This also ignore the effects on the ocean life. As a side note, CO2 levels of 1000ppm or higher have been demonstrated to cause cognitive decline in humans and gets much worse at even higher levels.

    2. I agree with your assessment. The EPA, NASA, NOAA, IPCC etc are all pushing the ‘climate change’ narrative.

      NASA even changed their original website of their study, downplaying and minimizing the beneficial effects of CO2 fertilization.

      The above article is filled with unproven assumptions–and their claim to have ‘missed’ the activities of two of the largest and most populous nations on Earth does not inspire confidence.

      Princeton Physicist Dr. William Happer is an expert on CO2–check out his opinions on YouTube–if they have not yet been censored.

  5. Agree that increased crops do cause planetary greening and do not significantly alter the CO2 nature in the atmosphere since crops are used quickly and their products are recycled just as quickly. However, as with any process, you cannot get more out than what was input, but can get less out than was input (unrecoverable waste) which will take longer to recycle. This creates a lag which should be considered in any model.
    Reforestation and new forestation can be significant sinks for planetary carbon as long as they can retain the carbon for at least 8-12 years. Also, any forest products that fall into a reducing environment or are converted (by humans) into longer-term products essentially remove carbon from the cycle for even longer periods. While the IPCC claims that human-generated CO2 can stay in the atmosphere for 100 years, over 250 other peer-reviewed climate papers claim that 8-12 years is a more appropriate number.
    As a procedural note, while models may provide insight into the operation and responses of a system, any model used for prediction should only be used for such once validated by closely replicating the past and by agreeing with verified experiments. Data is paramount, but data is available in the past as well as the present.
    Earth climate change is indeed an important and complex process. The scientific community would do well to remember that climate change on Earth has been going on for over 4 billion years. Sea level, average temperature, and atmospheric CO2 concentration all have been rising at various rates (sometimes faster than current rates) for the past 21,000 years since the end of the last glacial period, and long before the presence of seven billion inhabitants and burning fossil fuels.

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