Is Netflix's Seaspiracy film right about fishing damaging oceans?

The explanation for the change in temperature that has by far the best evidence is the increase in greenhouse gas concentration in the atmosphere. We can derive this from physics principles and test it by examining CO2 concentration and temperature over long periods of time. CO2 concentration increases are coming from human emissions. This can be proven by examining isotope ratios in the CO2 in the atmosphere. Once we have this connection established, we can estimate future CO2 emissions and run models to predict future temperatures.

Rising temperatures are bad for a number of reasons

1. Certain staple crops are fragile and rising temperatures may turn highly populated regions into places where it is difficult to grow enough food to feed the population.

2. Sea ice melt increases water levels, threatening coastal cities and reducing global albedo.

3. Certain macro weather patterns like the gulf stream are found to be unstable in models if we increase the temperature. This has big problems for places like Europe, which are made warmer than their latitude would suggest by these macro weather patterns. A similar situation occurs in California where the RRR breakup allows for wet winters and if it fails to break up (more common in higher temperatures) then we get bad droughts in CA. This effect also contributes to the polar vortex that causes major cold snaps over the central US.

Changes in these macro patterns are what enable the sort of "my winter was cold, where is the warming" effects.

Human beings could adjust where we live and grow crops to account for rising temperatures. But this is massively expensive and disruptive and does not work well in a world where state borders are fixed on a map. This "solution" is not especially viable.

4. There are some hypotheses that increasing temperatures can cause an unstoppable positive feedback loop, as lower albedo means we absorb more sunlight and releasing gasses trapped in ice means that greenhouse gas concentration will increase even if human emissions drop to zero once we are past some tipping point. These are not proven hypotheses, but they are worth considering.

The film was pretty sympathetic to those communities. In particular, coastal Africans, who depended on local fish for food, and now are in trouble because industrial fishing operations are vacuuming up those fish.

The main point of disagreement in the article is the study about 2048. It's good news that the future might not be quite so imminently grim, but the film doesn't lean on the study all that much. For the other claims mentioned in the article, it says the film was pretty accurate.

So contrary to Betteridge's law, it appears the answer to the question is "mostly yes."

You can just point them at https://skepticalscience.com/oneliners.php for a lengthy list of the arguments they're going to use and the trivial reasons why they're wrong, but it doesn't get at the core of the problem: you can't reason somebody out of a place they didn't reason themselves into.

I know that cigarettes are bad for my lungs and for my heart. How do I know that? Because I can read ONE COMMON OPINION everywhere. All the time. Nobody claims it is good.

Global warming? I hear everything pro and con and then more.

Your answer is essentially: go learn something because it is true.

The funny part? I know very well this is true. How? Where to look for the ELI5 version? No idea.

Suppose one moment you are not an expert in quantum mechanics, especially the multiverse model. Out of your head, where are you going to go to learn about that? Wikipedia? OK, let's see the "Scientific consensus and society" part for global warming. Lines and lines of explanation that all scientists say it is true.

Do you see something like that elsewhere? No? So it means that the topic is far, far from being obvious and that we should have a good campaign, oriented to normal people such as myself (and not erudits such as you) to explain it clearly. I live in France and I have not seen one such campaign.

So much for awareness.

Your position is exactly what drives people away from science: "With your level of education it shouldn't be at all difficult to find a resource that answers your questions. Instead you've sought out two comic strips and two extremely ideological sources.", "Again, this has all been said thousands of times. If it helps to have somebody explain it to you, great." etc.

Have you ever taught others? Well I did for years and telling them "you dumb people, you should know this so move your ass and learn" is not going to help.

Of course I (as in me personally) know how global warming works. My neighbours do not. Because what they hear is "you should know because it is simple"

You say you are frustrated. I spent 30 years pushing science into the head of people, either willingly or not (-I mean the receivers of the science :)). I fought pseudo science. I tried to teach what I knew.

I am not a specialist in climate and my understanding is a bit above your "this is very simple" part (I would add the physics and the complexity of simulations in the "I get that" part). But I am not equipped to evangelize the topic. And I see that other are not either because I did not hear about it eanough so that it is obvious fore everyone listening.

is it for beef cattle? palm oil? vegetables? lumber?