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Comment by zosima | Hacker News Reader

1. The graph is apparently adjusted for CPI, but not house prices. House prices especially in big cities has mostly gone up much more than CPI over time. [1]

2. Including only billion dollars climate events does seem misleading and especially prone to statistical bias. Both bias towards local weather around cities, but also for modern days, partly because of 1.

3. Population has gone up and cities expanded so there's now a much larger area to make billion dollars devastation on.

Using percentage of GDP and not setting an arbitrary threshold of a billion dollars would rectify some of these problems. An alternative graph is provided here [2], and on that it's much harder to spot a trend.

[1] https://www.bankingstrategist.com/housing-prices-hpi-vs-cpi

[2] https://www.forbes.com/sites/rogerpielke/2019/11/07/everythi...

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Florida is one of the places I look for when it comes to this. According to the NOAA [1] they have not really been able to detect an increase in hurricanes (the natural disaster that semi-regularly hits Florida) due to climate change. Yet, there has been growth in GDP and population. So, the increase cost in Florida is, at least in part, due to the increase in what people have.

If we have more and more expensive things (especially nice buildings) it's going to cost more even when the weather stays relatively the same.

Disclaimer, I'm not making a statement on climate change. I use FL as an example to highlight a different point. In the reference you'll see there is talk of places where observations of change have occurred.

[1] https://www.gfdl.noaa.gov/global-warming-and-hurricanes/

> they have not really been able to detect an increase in hurricanes (the natural disaster that semi-regularly hits Florida) due to climate change

Correct, not a significant increase in the number of hurricanes, but they are projecting an increase in destructive power.

> The IPCC AR5 presents a strong body of scientific evidence that most of the global warming observed over the past half century is very likely due to human-caused greenhouse gas emissions.

> it is likely that greenhouse warming will cause hurricanes in the coming century to be more intense globally and have higher rainfall rates than present-day hurricanes.

> the lifetime maximum intensity of Atlantic hurricanes will increase by about 5% during the 21st century

> We also conclude that it is likely that climate warming will cause Atlantic hurricanes in the coming century have higher rainfall rates than present-day hurricanes, and medium confidence that they will be more intense (higher peak winds and lower central pressures) on average.

The original article was about cost of damage from storms. It was looking at the past. If the atlantic basin has not yet seen an increase in number of hurricanes or intensity of them than that's important when looking at the reason for storm damage costs. We can't yet say the increase in cost is due to hurricanes.

Projections on future increases (which concern me) do not have an effect on already observed costs. I know places where this point is lost.

> they are projecting an increase in destructive power.

Is this being measured by wind forces, tidal surges, etc?

Mostly higher rainfall / flooding (due to warmer waters).

For wind, it sounds modest. They project the strongest hurricanes to be 5% stronger (windier) by 2100 than the strongest hurricanes today.

Of course there are other factors too like sea level rise which isn't factored in I don't think. If your city is already flooded and a hurricane hits, I'd imagine the damage would be worse or last for longer.

There has not been an increase in frequency of hurricanes, but there has been an increase in the energy carried by hurricanes and hurricanes intensify faster than they used to. It is wrong to imply all of the increase in damages is due to economic growth.

https://e360.yale.edu/digest/atlantic-hurricanes-are-becomin...

Seeing as the cause of these disasters is economic in nature I fail to see how this is misleading.

Well, if you want to know the total economic loss due to weather, you might also want to e.g. include $900 million events.

If you want to know whether there is more disastrous weather in general, you probably don't want to completely ignore the vast majority of land. (Where destruction amounting to $1 billion is fairly unlikely)

For almost all interesting questions around changing trends in catastrophic weather's effect on the economy, I'd want a different measurement. What would you think, you could use this for?

Tools like these, while perhaps only answering very specific and limited questions, can be really useful when explaining phenomena to decision makers. More often than not (at least in America), the financial impact carries the most weight, particularly to those who might otherwise not care at all about climate change.

But what conclusion will decisionmakers draw? That climate change is something we need to address urgently, or that our population densities have grown and maybe we need to consider that in disaster planning?

But why not make the data as unbiased as possible? Why not show total cost for weather events as a percentage of GDP?

Or if only large-scale catastrophes have increased, the distribution of weather events?

Or maybe the percentage of houses destroyed or the total acres of land rendered temporarily useless?

Or number of weather-related casualties per capita?

While none of those are perfect or complete measurements, they'd all dodge several issues discussed here.

One interpretation implies the weather is getting worse(equally costly stuff). The other implies people just have more costly stuff(same weather pattern).

Both interpretations would be wrong because it's not either or. It's both.

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