Aligning Tide Gauge Stations

I’ve spoken before about my new way of aligning tide gauge stations. Maybe it’s time for me to outline some of the details, and share my program (written in R) for doing the computation.

Sea Level Acceleration since the 1960s

Dangendorf et al. have made a new estimate of global sea level since the year 1900, based on data from tide gauges around the world. I’ve compared it (which I’ll call Dang) to the most trusted data set (in my opinion) from Church & White (which I’ll call CW), to the dataset I have criticized from Jevrejeva et al. (which I’ll call Jev), and to my own reconstruction (which I’ll call me) based on my own method of correcting for VLM (Vertical Land Movement). The first thing to note is that my own data doesn’t include proper area weighting, and can only be considered seriously flawed. But it is my own, so we’ll see how the new kid on the block compares to it, as well as to well-known data sets. Here’s the new data from Dang:

Sea Level Acceleration Denial

Dave Burton, you still don’t understand.

You finally commented on this post, showing a graph of San Diego data and saying:

As you can see, there’ve been >112 years of continuous measurements, and still no detectable acceleration.

Not true. I detected acceleration. You don’t believe it. Then you gave us this:

Sea Level Acceleration

Dave Burton has visited, and commented extensively on this post. He takes exception to the sea level data I used, and suggests that sea level has been rising at a steady, unchanging rate “since the late 1920s.” To quote him:

Neil, many locations have seen a little bit of acceleration “since the 1800s” — but not since the late 1920s.

Is that true? I’m skeptical.

Global Temperature Evolution 1950 to 2018

It’s been a while since Foster & Rahmstorf (2011) took global temperature time series and removed our best estimate of the changes due to known fluctuating factors, the el Niño Southern Oscillation (ENSO), aerosols from volcanic eruptions, and variations in the output of the sun. After removing fluctuations of known origin, what was left over was a very steady rise in global temperature.

I’ve improved (I believe) the method by allowing for more detail in the response to ENSO. I now allow both a “prompt” (not necessarily immediate) and “more delayed” response, as well as a seasonal pattern to the ENSO response. I’ll probably expound on those details at some point, but not now. Now, let’s look at the results.

Sea Level Rise

The streets flood even without storm, rain, wind, even on a calm sunny day. It didn’t used to happen, but now the highest spring tides of the year (around October) bring flood waters, septic systems back up, waste oozes onto streets and lawns, saltwater leaks into groundwater and spoils drinking supplies. It’s not a pretty sight, and it’s not confined to Miami and New Orleans, it’s all along the coast.

It’s an undeniable sign sea level is rising. But one wonders: how fast?

Young Girls Save the World

The lack of action about climate change by politicians, by adults, largely by old men (like me) is depressing. Truly depressing. From time to time I need some inspiration, some actual hope that the world can turn this around.

We DO have hope. Thanks to girls.

Please follow the link and read it. You’ll be glad you did!

Climate Deniers: Long-Term Annoyance

Climate deniers Ross McKitrick and John Christy have published an article in the Journal of Hydrology which demostrates to those who know what they’re doing, that McKitrick and Christy don’t. If you really don’t know what you’re doing you might think this paper is impressive. If you do know what you’re doing, this paper is a supreme embarrassment to its authors. It’s a supreme embarrassment to the reviewers who approved its publication — they too can’t know what they’re doing. This paper is that bad.

Climate Change: in Vino Veritas

In truly fascinating new reasearch, scientists have searched historical records to collect data about when the grape harvest began each year. Their research wasn’t published in the Journal of French Wine (I don’t know if there even is one), it was published in the journal Climate of the Past. That’s because the date when the grape harvest begins is a clue to temperature.

The importance of clues like this is that they extend farther back in time than thermometer records. The grape harvest dates (GHD) start in the year 1354 — centuries before the thermometer was even invented. Also quite important: they are all for the same location: Beaune, France.

When the temperature is hotter, the grapes are ready to harvest earlier. When it’s colder, they harvest later. If climate is really heating up, the grape harvest should be getting earlier. And what did they find? This:

Climate Deniers Deny Temperature Itself

There’s a lot of talk these days about global temperature, in news reports, policy discussions, and casual conversation. The global temperature under discussion is surface air temperature (SAT). It’s not the depths of the ocean — even though that’s really a better measure of global warming, we don’t live in the depths of the ocean. It’s not the temperature in the upper atmosphere, we don’t live in the upper atmosphere. It’s the temperature at Earth’s surface. That is, after all, where we live.

But climate deniers don’t like that, because surface air temperature has risen so dramatically these last few years. Someone proclaims “The last five years have been the hottest on record!” and the deniers want to deny it, but they can’t use actual data for SAT because the data support the statement. But there’s a sneaky way for them to try: look for some data set — ANY data set — which you can claim represents “global temperature” but contradicts the “last five years” claim. If instead of claiming it’s global temperature, you simply say nothing at all about it so readers assume so, even better. If that data set happens to be crap — best yet!