No. Global cooling was never a serious scientific line of study and easily refuted with 30 seconds of effort on the internet. But I'm sure it's just easier to go by what conservative media says.

There have been studies showing that research usually supports the money behind the study. The government (politicians) has an agenda just as much as the private sector. The bulk of research funding comes from government grants. Research centers know that they are more likely to receive funding for a study to support a given narrative rather than one to debunk that narrative.

Politicians aren’t in bed with coal or green companies to a degree that would change anything. They are in bed with voters and will say what ever their base wants to hear even though they know that the math just doesn’t work. The more radical ideas being floated around such as the green new deal are examples. Our energy demands are too massive for wind, solar, or hydro power to even make dent in our needed supply. Politicians are afraid of the only green option capable of actually meeting demand, nuclear power. As a result we fire up fossil fuel generators which are our only remaining option capable of meeting demand.

The bottom line is that our demand for energy is massive and our green options are severely limited due to our current technology. As far as the original focus of this thread, flight shaming, there is no clean alternative. Unless we come up with a new method of propulsion, we’re going to burn millions of gallons of fuel every day. The same goes with all of the transportation sectors. It takes a massive amount of petroleum to produce our food and ship it to the consumer, to produce goods and transport them, etc. We’re a long, long way from being able to make anything but a token attempt at actually reducing the environmental impact of burning fossil fuels, but that token attempt seems to be enough to fuel various political/public agendas.

It has nothing to do with liberal vs conservative. Climate change has become an almost religious obsession, both for and against, based more on ideology than science. Yes the stuff that we pump into the atmosphere contributes to the equation, but we are incapable of actually changing much of anything. We could cut our fossil fuel consumption in half overnight and we wouldn’t even bump the needle over time. There is a great clip by George Carlin on the environment that sums it up pretty well. It has some profanity in it, so I won’t provide the link, but you can google it. The earth is millions of years old. It has survived meteor bombardments and massive extinctions during that time and it keeps on adapting and chugging along. Man’s influence is but an insignificant blip, but our arrogance in thinking that we can manage nature is impressive.

Actually we have the technology today to massively reduce aviation petroleum consumption with carbon neutral-ish drop-in fuels.

There are a LOT of potential options, many of which have demonstrated on revenue flights.

Traditional biofuel from plants: Would take a lot of real-estate, not sure how much exactly. Preferred plants thrive in desert environments so they're not competing with foodstock. This can be purchased today in boutique quantities.

Algea biofuel: Advantage that it can be grown in artificial environments, with artificial light if needed. Don't need X square feet of land to collect Y amount of sunlight so the farm can have a vastly higher output density for a given amount of real-estate. Artificial light would require grid power, ideally green or nuclear. But even grid power from a fossil plant is going to produce less emissions than a jet engine... fossil plants are optimized to an extreme degree for fuel efficiency, while jet engines have many necessary comprises. Same way a Tesla theoretically produces less carbon that an IC car.

Waste biomass fuel: If all of the convertible waste (ie landfill) were captured, a rough SWAG is that it would be more than enough to provide fuel for all of aviation, plus trains, trucks, ships, etc.

The conversion processes for all of these are well established, the challenge is supply, demand, and economics. Currently the cost would be 2-5 times Jet A (Jet A/petroleum prices could easily fluctuate higher in the future but probably won't ever be much lower than now on a sustained basis). Economy of scale would reduce the cost delta, conservatively to somewhere between 1-2 times jet A cost. Would have the advantage of being price stable and predictable as well.

There are potential regulatory mechanisms to phase in biofuel use in a manner that would make economic sense. For example, require airlines to use a very small % of biofuel, and then gradually increase that % over a period of years. That would initially incentive supply growth, and keep it growing at a sustainable pace. The big problem with biofuel utilization is incentivizing supply ramp-up. But even without regulatory mandates, some airlines will start doing it anyway.

Biofuel can run at up to a 50% mix with jet A. The plane's fuel system were designed for jet A, and need some to lubricate some parts and keep some seals pliable. Presumably you could go higher than 50%, not sure how much higher. Future aircraft could readily be designed with minor tweaks for 100% biofuel.

It's ready to happen now, somebody just needs to pull the trigger. That will be driven by politics, regardless of how you feel about the science, so if you're in aviation you're along for the ride.

Now we get to some things which are a little further away, but which may have the potential for greater impact.

Synthetic Fuel: Create fuel from scratch, all you need is air (carbon from Co2), water (Hydrogen), and power. This can be done now, they are refining the process for scale and economics. Very small footprint for the output, no issues with land or food, and almost no logistics/infrastructure overhead other than the plant and existing delivery systems (mostly pipelines). With nuclear power, this would be as close to zero net carbon as you can probably get. You could even achieve net negative carbon if you added carbon-capture to the system (at some extra cost of course).

Even further out there, lockheed-martin is working on what they claim is a near-term practical compact fusion reactor, scalable to a size and power density that would work for commercial aircraft (among many other things). I know, fusion is always 20 years away, but this one actually looks more promising. I'm not really holding my breath, but this would be a huge game changer, literally solving most emissions and carbon issues overnight. It would also make a very useful spacecraft engine...

You’re absolutely correct on the various biofuels, but are they a fiscal reality at this point? Not only in price per gallon, but can we actually produce enough gallons? I’m not playing devils advocate, I really don’t know the answer. I read a report a few years ago showing that United alone burned around 8-9 million gallons of fuel per day. The amount of fuel consumed in the aviation industry is mind blowing. If we can actually produce enough for a market supported price, then I’m all for it. If the price of that fuel is significantly higher and the use was mandated by a government order, air travel would become too expensive for most Americans, and we’d be looking for work. Any change will have to come in increments due to cost and supply. The market would adapt, but increasing the cost of aviation will reduce the demand to some degree as well. Lowered demand for air travel would solve the airport congestion problem though.

But it has also had some serious environmental swings along the way, including mass extinctions.


We can most certainly manage nature with our current technology. The questions are does it need to be managed, how much, in what direction, and who are the winners and losers?

We have changed nature incidentally through mass industrial systems... if we put our mind to it and employed systems intended to DELIBERATELY change the environment, it would change all right.

In fact I know how to easily nearly destroy the biosphere and most complex life on the planet. I could do that with commercially available advanced technology and maybe as little as $300M dollars, as long as nobody was paying too much attention. Don't need plutonium, or anything else that's really controlled. I'm certainly not going to say how in public but if you're interested pmail me.

I’m interested, and will give you a cut of the Billion dollars the World will pay me to not destroy it.

Dr. Evil :p

You plan on killing all the bees with your chemtrails?

WG3 was written specifically to look at the impacts and mitigation strategies. Public policy is a massive part of that, so of course it has guidance to that end. It's also not remotely the same thing as WG1, which is the Physical Science Basis. Go look at the thousands upon thousands of peer-reviewed citations in WG1 and see how many of them have political guidance. The answer will be close to, if not, zero.

There is a functional difference between science and policy. The IPCC doesn't hide from that at all. It's why they compile three different reports. One that describes the current scientific understanding of climate change, and contains over 5,000 peer-reviewed citations of scientific papers, one that discusses impacts and vulnerabilities, and one that discusses mitigation. It's an exceptionally comprehensive document that synthesizes existing knowledge on the topic across a wide range of disciplines, ranging from the physical sciences to social sciences and public policy. Necessarily, there will be discussions of appropriate methods for dealing with the impacts of climate change. That isn't led by physical scientists, it's led by social scientists/policymakers.

What you're saying is a strawman, because climate scientists, that is, climatologists, atmospheric scientists, physicists, etc. are not the ones preparing WG3. They may be tangentially involved, but it's as a function of their research in their academic discipline.

I'm fine with nuclear as a stopgap, but fundamentally it suffers from the same issues that fossil fuels do. The emphasis needs to transition away from non-renewables.