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Comment by gravelc | Hacker News Reader

> I find it far easier to believe that the consistent global drop in insect populations has far more to do with deforestation and chemical disbursement rather than fractions of degrees of warming that we've seen so far.

You might find it easier to believe, but that doesn't make it so. Ecosystems are interconnected. A degree of warming might not do much to a loan insect in a cage, but a degree can contribute a lot to the spread and range of bacterial and fungal pathogens of insects. It can change how plants behave (they can't get up and move, so have to respond physiologically to survive in the same location), and that change impacts insects. Competitors for the same resources may respond better to temperature rise or other climate related changes. Climate change also changes farmers' behaviour - more pests due to warmer conditions can mean more sprays, which have unintended consequences.

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we've seen about 1.5 degrees fahrenheit of warming so far.

It seems that people seriously struggle to understand how significant a single degree change in average temperature is.

We're wired for short-term thinking and this is a good example of it. When someone hears '4 degrees of warming' they think of what 4 degrees change feels like to them in the context of a day. Which is to say, not much. Sounds kinda nice. Same thing with sea level rises. We think of a shoreline we are familiar with, and consider a future for that place where the water level is a few feet higher. Chances are what's being pictured looks like no big deal.

A person would have to make the choice to actively investigate further the marginal effects of such a change, the impact from the rate of change, and points that are less obvious such as global temperature averages incorporating the 70%-of-the-surface heatsink that is the world's oceans. That kind of prompting for further thinking is for sure already happening in classrooms worldwide, and is one of the reasons there's such a stark difference in opinions on the issue as you look across the age brackets.

One way to tackle this might be better messaging, but looking back over the attempts to pivot on that front (global warming -> Climate change) and how much of an easy target that became for criticism, I'm not hopeful.

I wonder if there would be a greater impact on the way people think about climate change if the messaging was more specific to the places in which the audience lived? For sure a big challenge here will be accuracy, even if it's possible to bring the conversation down to that level.

I know I do, and part of the problem is that everyone deals with temperature every day, so it is an uphill battle trying to get across just how dramatic a 1 degree change is. It's one degree (Celsius or 1.8°F) but my house's temperature differs by more than that from room to room, and I don't normally notice that difference. Nor does a 1 degree difference in the weather materially change how hot/cold I feel. I feel freezing cold at -1, 0, or 1°C, even though pure water won't technically freeze until it hits 0°.

Another difficulty because it's an average over time, is there's nothing I can look at to see where we are right now - the average temperature of the world right this second isn't particularly meaningful compared against the 1 degree line that we're measuring against.

When the question of why 1 degree is so significant comes up, we can sidebar to explain just how catastrophic one degree is, but the layperson isn't always up for rigorous scientific discourse. Hell, we renamed "global warming" to be "global climate change" because of the 'joke' that global warming can't be real because it's still cold in winter (and it's still not gone away). I am unconvinced that having to explain why 1 degree is catastrophic is doing us any favors, especially considering that the average temperature rise is usually presented with one or two significant figures.

What then? Short of changing human nature, which we've been trying to do for years, one possibility is to pick a different measurement, or to give additional numbers for effect. In this case, the reason the one degree change is due to how much has to be heated for that single degree change. The entire atmosphere, the water, and surface all have to warm by one degree. How much is that, actually?

Is there a standard "Earth" surface area to get the right order of magnitude for just how much extra energy 1 degree is? How much energy would it take to heat this entire Earth 1 degree? We're talking on the order of zettajoules, at least. In imperial units we're talking gigatons of TNT, or petaBTUs.

For the last point I saw that to heat the oceans as fast as we are it would take a nuclear bomb worth of energy set off every second for the last few decades.

Useful for many people but even this is a bit frustating - 1 fat man or little boy, or 1 tsar bomba?

One thing that helps for me is to consider the bell curve profile, and the fact that a small shift greatly increases the area under the upper tail part of the curve where the extreme weather events live, eg:

https://www.climatecentral.org/gallery/graphics/small-change...

It does require some ability to grasp the concept of these nonlinear effects, so might be an uphill battle, depending on who you are talking to.

I think a good example is that average normal body temperature is 98.6 F (37 C) degrees, but if you have a high-grade fever which is around 103 F (39 C) degrees, you're feeling very ill, even though it's just a small raise in temperature.

A single degree increase is significant because that suggests soon it will be 2, and then 4 and then 8... etc etc

The real worry is when we get to 8 degree increase which based on everywhere we've looked in the world that suffers from a 105+ degree avg temperatures tends to suffer from sparse plant life.

Though with that being said, our assumptions about that being what happens to the whole planet if our summers on average get to be 105f on average is very very very very speculative and actually counter intuitive in the sense that one would assume that with increase temperatures you should assume more water evaporates all over the globe, and therefore more rain should occur.

Nobody has pointed out the just as likely possibility, that perhaps global warming might be a problem that fixes itself. (i.e the amazon and africa is warmer because its closest to the equator therefore it has the most densely populated plant life) That is of course after all the Democrat's real estate ends up under water. ^_^ jk jk

My point basically boils down to this, we obviously don't want to continue this trend for the next 100 years. But you could also make the argument that if we could make the planet hotter by a few a degrees and put a cap on the increase in heat, the rest of the planet should naturally become more amazonian/african habitat. Which I don't see how that is necessarily a bad thing considering that is essentially how nature is designed to balance itself out.

To understand the consequences of global warming to the fullest its worth pointing out that we need to understand how ice ages can occur and dissipate in the first place. In that phenomena we see that there is a natural balance that is occurring where nature has a way to modulate exorbitant CO2 output of animals in relation to the plant life. When trees grow in abundance and there isn't enough animals to breath o2 and produce co2 obviously the planet eventually over thousands of years grows so cold that plantlife gets concentrated to the equator. And then with evolution animals get bigger and more plentiful and therefore starts breathing more of the o2, producing more co2, the point being there has to an inequality where animals per mass consume more O2 molecules as a biological function than a plant consumes CO2. (which kinda makes sense if you think about the whole "circle of life" of cellular biology.)

That is the only way such climate changes could occur when the planet's orbit never changes in distance from the sun.

These climate changes occur reeeeeeally slow and of course that means its in an intricate balance with the slow process of evolution... but still with that being said we assume climate change is going to be a calamity only to us, but that doesn't mean its going to necessarily be something that the earth isn't already very well prepared to resolve on its own after were gone. And if it can save it self, that means we can just make sure we save ourselves by burying fallout esque vaults under ground, or going to Mars.

Is that true? I thought we were still below a degree, but had just reached the point where 1.5 was inevitable later due to delayed effects. That was depressing when I figured out that even if the world became carbon-neutral tomorrow we'd still be getting warmer for a while.

We are below 1 degree Celsius. 1.5F is about 0.9C.

Those second and third order effects might be easier for you to believe, but until there is evidence pointing to that being the cause, shouldn’t pesticides be pretty suspect?

I didn't state otherwise.

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