to clarify, my comments start at -Before 1900 ..

Indyvidual,

Yes, global sea levels have risen about 0.20 to 0.30 metres since 1800, with a significant acceleration in the last century. This rise aligns closely with the increase in greenhouse gas emissions, rather than just natural variability.

The impact that shipping has on sea levels is miniscule. It contributes only fractions of millimetres - not centimetres. The main drivers of sea level rise are thermal expansion of seawater and the melting of land ice.

Land reclamation and subsidence are factors that only affect certain areas on a local level. They don’t explain the global rise. Subsidence worsens the effects of sea rise in specific regions, but the consistent rise worldwide is almost entirely due to climate change.

Natural instability and fluctuations play a role, but the global, consistent trend in sea level rise points clearly to human activity as the main cause.

Local factors like subsidence and land reclamation matter, but they don’t contradict or account for the broader global trends driven by climate change. But if you think you know better than the thousands of scientists who understand all of this, then write a paper citing your research and earn yourself a Nobel prize.

Struth, its like trying to hold rancid custard in one hand - it keeps leaking through because there is no substance.

JD starts of claiming the sea levels were "stable sea levels until around 1900". When I push back he immediately caves with "the graph does show minor fluctuations in sea levels over the last 2,000 years". Minor is in the eye of the beholder. (I wonder if the Dutch building the dykes around 1000AD thought it was minor?)

Then he looks at the graph and decides that the rise started around 1950. The actual authors of the paper containing the graph wrote..."Historic GSL rise began in the 19th century, and it is very likely (P>=; 0.93) that GSL has risen over every 40-y interval since 1860 CE. " oops.

Then he claims that the " islands discussed are exceptions" and when I point out that they'd looked at 1000 islands, he say "So what?" and hurries to move off on a tangent. The fact is sea level change isn't affecting these islands. Or more exactly its one of many players. Islands grow and recede or do neither for all sorts of reasons. But the alarmists only want to look at those that recede or can be misconstrued as receding and then to blame it entirely on warming. When all the evidence, a mere fraction of which I've shown, doesn't support that at all.

What I find most interesting is that JD will happily throw ad hominems around like confetti, but as soon as someone looks sideways at him, gets all sooky.

Speaking of ad hominems..."you are a denier, not a sceptic."

To those who've bought the scare without having too much understanding of the data, everyone who isn't similarly alarmist is a denier. The fact is there are very few deniers as in people who deny climate change. But that'll be ignored.

Like most people who JD would call a denier, I don't disagree that the temperatures have been rising since the end of the Dalton Minimum. Equally I don't deny that man has played some role in the rise through gases like CO2 and methane. But I don't agree that all the rise was caused by man.

More importantly I don't agree that the rise has been dangerous for humankind or the planet, instead thinking it has been beneficial. I also don't agree with the alarmist claims that future rises will dangerous, instead thinking they'll be minor and probably beneficial.

Most importantly I don't think there's the slightest need right now to do anything about the recent rises. The monumental sums expended to fight a non-problem are among the greatest errors ever made by human society (really western society because the rest of the world hasn't fallen for this malarkey). Instead I favour a no-regrets policy of climate mitigation.

mhaze,

It appears I was STILL giving you too much credit. I do like how you can’t address your comments to me, though. It’s a sure sign of cognitive dissonance and high anxiety in an online debate when someone instead speaks to an imagined audience.

You’re still cherry-picking data and interpreting it to fit your narrative, too, I see. It’s a hallmark of denialism.

Speaking of which, I’m not using the term “denier” as an insult. Snowflake. So, it’s not an ad hominem. I’m also addressing your claims at the same time, so there’s yet another level on which it’s not an ad hominem.

With that out of the way, let’s take a look at what you’ve honed in on while missing the bigger picture.

1. Sea level fluctuations vs. stability:

The minor fluctuations over the past 2,000 years were within a stable range. What matters is the overall trend, and the data is unequivocal: the rapid, sustained rise in sea levels post-1900 is unprecedented. This is not just a continuation of natural variability - this is a clear departure, driven by human activity. Comparing today’s rapid increase to historical fluctuations is like comparing a calm pond to a rising tide; the difference in scale and impact is enormous.

2. Timing of sea level rise:

Yes, the rise began in the 19th century, but the sharp acceleration post-1950 aligns with industrial activity and CO2 emissions. This acceleration is what’s alarming and clearly linked to human actions, not just natural variability.

Oops.

3. Island studies and sea level impact:

The fact that the study examined 1000 islands and found variability doesn’t change the reality that sea level rise is a significant threat. Yes, some islands are growing, but others are not, and many are facing serious challenges like erosion, saltwater intrusion, and reduced habitability. Cherry-picking examples of growth doesn’t negate the broader risks posed by rising seas. The exceptions you point to are just that - exceptions. The overall trend remains clear: sea level rise is a growing threat, exacerbated by climate change.

I await your next delicious cherries.

I await your next delicious cherries.
John Daysh,
The studies results data you provide sound as good as any millions of Taxpayers Dollars can produce.
My question is, how correct is this data ? You say shipping displacement (770,000,000 square kilometres ÷ 20 + billion tonnes artificial displacement) amounting to several mm is insignificant yet you use numbers like 0.1-0.2 mm of sea level rise over long periods & make them look significant.
Science is only as accurate as the continued flow of funding so far as I can see. If rising sea levels are such an imminent threat why don't scientists offer solutions rather than perpetual assured funding alarm ? Changing the climate ?