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Comment by sanxiyn | Hacker News Reader

Scientific consensus, as published by IPCC AR5, is that there was no clear change in floods, droughts, storms in the last century. People are often surprised to find this because of sensational media reports, but that's what we have.

https://scienceofdoom.com/2017/02/12/impacts-v-climate-chang... has detailed discussion.

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But you're leaving out the more important part (per the NOAA summary):

Anthropogenic warming by the end of the 21st century will likely cause tropical cyclones globally to be more intense on average (by 2 to 11% according to model projections for an IPCC A1B scenario). This change would imply an even larger percentage increase in the destructive potential per storm, assuming no reduction in storm size.

There are better than even odds that anthropogenic warming over the next century will lead to an increase in the occurrence of very intense tropical cyclone in some basins–an increase that would be substantially larger in percentage terms than the 2-11% increase in the average storm intensity. This increase in intense storm occurrence is projected despite a likely decrease (or little change) in the global numbers of all tropical cyclones.

Anthropogenic warming by the end of the 21st century will likely cause tropical cyclones to have substantially higher rainfall rates than present-day ones, with a model-projected increase of about 10-15% for rainfall rates averaged within about 100 km of the storm center.

Here's a table of the number of category 4 or 5 Atlantic hurricanes broken down by year range. Note that the first two rows are 50 year ranges, the next two are 25 year ranges, and the last is 18 years, so the import columns are the rate columns, which give the average number of storms per year of each category during the corresponding year range:

   Years     Cat 4     Cat 5     4 or 5
            Num Rate  Num Rate  Num Rate
 1851-1900   13 0.26    0 0.00   13 0.26
 1901-1950   29 0.58    8 0.16   37 0.74
 1951-1975   22 0.88    7 0.28   29 1.16
 1976-2000   24 0.96    7 0.27   31 1.24
 2001-2017   21 1.2    10 0.59   31 1.82

Data taken from Wikipedia lists of category 4 and category 5 Atlantic hurricanes:

https://en.wikipedia.org/wiki/List_of_Category_4_Atlantic_hu...

https://en.wikipedia.org/wiki/List_of_Category_5_Atlantic_hu...

How accurate and complete are measurements across these time periods?

Are more recent periods inherently going to have more hurricanes because we now have the capability to detect more hurricanes? How has measurement changed over the past 175 years?

Doesn't seem out of line with casual observations. The last really disastrous hurricane was Katrina and that was over a decade ago.

How disastrous a hurricane is depends both on how strong it is and where it goes.

Since Katrina there have been 4 Atlantic hurricanes (not counting Irma) that were as strong or stronger, and one that was just slightly weaker.

They all devastated places that they hit, but they managed to not hit any major large population areas so they did not cause as much damage as Katrina.

While maintaining human induced climate influence, I think it's important to remember coastal areas were not as populated 50, 100 years ago. So what might have affected 100,000 people 70 years ago might affect 500,000 today, given pip increases and urbanization and paving over (as opposed to historical gravel).

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