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Nasa Happily Reports the Earth Is Greener

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Re: Nasa Happily Reports the Earth Is Greener

#61

Would it be possible to turn a desert region into a rain forest? For example if Nevada decided to plant trees in the dessert is it possible with enough irrigation or would all the trees just die?

Some problems: 1.Forest fires within a dry climate(vs humid jungle). 2.If the water table is too deep, trees will need artificial irrigation, forever. 3.It seems easy to create a single-point of failure : monoculture of "best-performing" tree species which would succumb easily to specialized insects or fungus.

1. Forest fires need base fuel load to propagate. This is the organic matter at ground level, formed from the dead stuff that trees drop (leaves, branches, whole dead trees, etc). In other words, forest fires only happen in mature forests that are left alone to accumulate base fuel load.

2. Tree raise the water table under them, by providing shade (so water on the ground doesn't evaporate as quickly and gets a chance to soak into the ground). They also prevent water tables from surfacing (by drawing the water up from their root systems). In other words, a mature forest will manage the water table, rather than being managed by the water table. You get water table problems if you cut down too many trees. Growing more will solve that.

3. this is true. There are lots of ways around it, though, if your goal is to green the desert rather than creating lots of cheap timber quickly.

Re: Nasa Happily Reports the Earth Is Greener

#62

Serious question from a non-climate scientist: would an increase in global temperatures due to climate change ultimately cause more greenery, due to new growth in previously too-cold areas?

Another question on the same lines - wouldn't the increase in carbon dioxide also contribute to increased greenery? I guess the more pertinent question would be what amount of greenery could have a reasonable chance at halting the adverse effects of human activities?

Re: Nasa Happily Reports the Earth Is Greener

#63
post #58

https://www.nytimes.com/2018/07/30/science/climate-change-pl... "Despite global greening, carbon dioxide levels have climbed over the past two centuries to levels not seen on Earth for millions of years. And the carbon dioxide we’ve injected into the atmosphere is already having major impacts across the planet." The "global greening" effect, to the amount it can manifest itself, existed since the CO2 started to incre…

I kinda find it weird, though. Because we only know what prehistoric climate conditions were because of tree rings (and ice cores, but they're measuring different things).

So predicting future tree ring growth based on climate changes, when we estimate the historical climate based on tree ring growth, means we can make up any relationship we want.

Re: Nasa Happily Reports the Earth Is Greener

#64

Would it be possible to turn a desert region into a rain forest? For example if Nevada decided to plant trees in the dessert is it possible with enough irrigation or would all the trees just die?

Salt would be a problem in the low-lying areas, and irrigation can increase salinisation.

https://en.m.wikipedia.org/wiki/Dry_lake

https://en.m.wikipedia.org/wiki/Soil_salinity

Re: Nasa Happily Reports the Earth Is Greener

#65

Thanks for the good newss, didn’t know about that. News tend to be biased towards the bad and the good is left it. Bookmarking that site

It's greener because the vegetation is capturing some of our massive CO2 emissions, but the planet (or the biosphere, more precisely) is increasingly suffering from the Anthropocene: the ocean is slowly being killed, the soil is getting ravaged, insects are disappearing, birds too, the biodiversity is collapsing, etc.

A greener Earth is not a good sign. It's a swan song :'(

Re: Nasa Happily Reports the Earth Is Greener

#67
I wish there was an auto-downvote button for the tiresome garbarage of having to relate everything to climate change.

This has nothing to do with climate change as it states.

This is humans planting trees and forests which is normally thought of as good by normal people.

And efficient use of land to grow plants which should be thought of as good by intelligent people since it means we can cut down less trees to grow food.

People always seem to have to bring it back to their me me me religious climate change when it's humans who directly burn the world, or in this case have directly repaired the world.

Re: Nasa Happily Reports the Earth Is Greener

#68

From what I understand, the increase in atmospheric carbon dioxide will have a massive greening effect on the Earth (plants love CO2). But it seems this fact is usually omitted so as not to complicate the intended message. I always found it ironic that the "eco" mode button in many cars is a leaf icon.

> plants love CO2

In artifical conditions in laboratory there is a significant effect, up to 20% when doubling pre-industrial CO2 concentration.

But, in practice for wild plants nitrogen quickly becomes the bottleneck, so the real gains are much smaller.

And even for farming plants (which have fertilizer providing additional nitrogen) the real gains diminish, and are more in 5-10% range. For some crops CO2 has very little effect at all (for example corn).

Additionally - crops grew with raised CO2 levels have less proteins and useful nutrients.

And then you have to factor in the harmful effects from global warming on crops (heat damage, dry soil, less farmland available) and the overall effect is likely negative.

https://www.scientificamerican.com/article/ask-the-experts-d...

Re: Nasa Happily Reports the Earth Is Greener

#69
post #58

https://www.nytimes.com/2018/07/30/science/climate-change-pl... "Despite global greening, carbon dioxide levels have climbed over the past two centuries to levels not seen on Earth for millions of years. And the carbon dioxide we’ve injected into the atmosphere is already having major impacts across the planet." The "global greening" effect, to the amount it can manifest itself, existed since the CO2 started to incre…

I kinda find it weird, though. Because we only know what prehistoric climate conditions were because of tree rings (and ice cores, but they're measuring different things). So predicting future tree ring growth based on climate changes, when we estimate the historical climate based on tree ring growth, means we can make up any relationship we want.

That shows lack of understanding in purpose and use of the tree rings and it is not relevant to the topic. What I read from your statements is just that you don't understand how the past climates are scientifically reconstructed, and want to express the doubt in the results of all the work of all the scientist that agree (which is effectively all of them, minus the ones directly or indirectly funded by fossil fuel companies or motivated by political relations, if you have other impression, it's distorted by the intentional activity of said companies and political groups).

But we don't configure the current modeling systems at all using the "prehistoric" reconstructions, the models and the currently measured values are much more precise. The "prehistoric" reconstructions only give you something to compare the orders of magnitudes.

And comparing that, the warming is unprecedented. Which is not surprising giving that the humanity managed to extract and burn more then the half of all readily available oil from the Earth's crust in just 100 years.

That very oil in the crust is however a result of more than 4 billion of years of the Earth's existence.

If you’re reading this in some country like US, given that the average US car weights around 2 tonnes, your existence alone is probably responsible for the CO2 mass equivalent to the weight of 7–10 cars every year, and to the volume of CO2 which corresponds to the volume of more than 3000 cars.

And the CO2, even if it's invisible for us, is actually "black" for something important: it's blocking the part of the spectrum that would allow the Earth surface to cool off. That's how small concentrations of it, compared to some other stuff in the air, produce such a big effect.

The physics is simple and undeniable, and it's known that there will be always more problems caused by the growth of CO2 in the atmosphere which increases the surface temperature of the Earth.

Re: Nasa Happily Reports the Earth Is Greener

#70

Would it be possible to turn a desert region into a rain forest? For example if Nevada decided to plant trees in the dessert is it possible with enough irrigation or would all the trees just die?

I suspect it's about recreating the ecosystems rather than just planting trees and irrigating i.e. multi-decade process

Geoff Lawton's permaculture work on 'Greening the Desert" is well worth a watch e.g. https://www.youtube.com/watch?v=yI9wMtTvWps

(plenty more videos around if you search)

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