Sea Level Data: Church & White, or Jevrejeva et al.?

Before the satellite era, the best data we have about sea level comes from tide gauges. They give local sea level, which is the difference between the height of the sea surface and the height of the land (it can move up and down too). It is possible — but very complicated — to combine data from tide gauges around the world in order to estimate how global mean sea level (GMSL) has changed over the past century-and-a-half or so.

The two best-known such estimates come from two different teams of researchers; one from Church & White (which I’ll refer to as “cw”), the other from Jevrejeva et al. (which I’ll refer to as “jev”). Let’s compare them. Here they are:

Drowning in Sea Level Rise

It’s not likely that sea level rise will drown you personally. The sea is creeping up on us slowly, and yet — all too soon — it has already flooded streets even on sunny days, seeped into groundwater making it undrinkable, carried sewage from septic tanks onto lawns, even stranded an octupus in a parking garage (yes that really happened, on a calm sunny day even). It’s not just hurting coastal property values, it’s killing them.

But there’s one group that actually is drowning due to sea level rise: climate deniers.

Dum Dum Dum Dum Dum

I’m sometimes puzzled by GWPF (the “Global Warming Policy Foundation”). Do they think their readers are gullible idiots, or is the GWPF itself that stupid?

Sea Level Change on the U.S. East Coast, part 2

A tide gauge doesn’t measure the height of the sea surface; rather it measures the difference between the height of the sea and the that of the land. Thus is it sensitive to changes in sea surface height (SSH), and to vertical land movement (VLM) as well.

In the previous post I took sea level data from tide gauges on the east coast of the U.S., and computed a composite sea level record for each of four regions: New England, the northern mid-Atlantic, the southern mid-Atlantic, and Florida. Now that PSMSL (the Permanent Service for Mean Sea Level) has updated their database to include the latest complete year I recomputed my composites, using the data as is (not removing those periodic fluctuations I discussed previously, but yes removing the yearly cycle of the seasons by using anomaly values). And here are the regional time series, offset to make them easier to see:

Sea Level on the U.S. East Coast

Lately I’ve been looking closely at sea level time series from the east coast of the U.S. Available stations are marked here with red dots:

It’s real, it’s us, the risks are serious, and the window of time to prevent widespread dangerous impacts is closing fast.

WGBH Boston has produced an outstanding episode of NOVA about climate change. It’s realistic, it doesn’t give “equal time to idiots,” and it highlights the prospect of realistic solutions without soft-pedalling the problems. Definitely worth a watch.

This post’s title is a quote from Katharine Hayhoe, which is included in the show.

How Climate Deniers can “Hide the Incline”

Most of us have seen graphs of global temperature anomaly, like this one using data from NASA:

Recent Sea Level Change

NOAA provides an excellent website for acquiring and examining sea level data from tide gauges. It includes maps with which one can select individual stations, but which also show the rate of sea level rise based on fitting a linear trend to all the available data. Here’s their map, zoomed in on the USA:

Talking Points

The Huffington Post has obtained an internal memo from the EPA (under the leadership of Scott Pruitt) revealing what it thinks are the right “talking points” about climate change that can be “used across all Program and Regional Offices.”

The main point of these new “talking points” is to downplay global warming, chiefly by resorting to what I call the “know-nothing meme” — keep telling them we don’t really know anything. Yes something is happening, but we don’t really know anything about what the impact will be or what to do about it — if anything! Yes we’ve done extensive reserach, but we don’t really know anything because their are gaps in our understanding. We need to strive for a better understanding! Encourage more study and open debate, because we don’t really know anything.

What Scott Pruitt really doesn’t want his people to admit about global warming is that it’s real, it’s us, and it’s dangerous. Very dangerous. Of course there are gaps in our knowledge, plenty of them, but the fact that there’s a world of hurt headed our way and our actions will determine how bad it gets, isn’t one of them. If he admitted that, people might actually want to do something about it.

Here’s the text of the memo itself:

Dear Colleagues:

During the recent meeting of our Cross-EPA Work Group on Climate Adaptation, several individuals suggested it would be helpful to develop consistent messages about EPA’s climate adaptation efforts that could be used across all Program and Regional Offices. I’m pleased to report that the Office of Public Affairs (OPA) has developed a set of talking points about climate change that include several related to climate adaptation. These talking points were distributed today by Nancy Grantham (OPA) to the Communications Directors and the Regional Public Affairs Directors.

The following are the talking points distributed by OPA. I have highlighted those relating specifically to our adaptation work.

EPA recognizes the challenges that communities face in adapting to a changing climate.

EPA works with state, local, and tribal governments to improve infrastructure to protect against the consequences of climate change and natural disasters.

EPA also promotes science that helps inform states, municipalities, and tribes on how to plan for and respond to extreme events and environmental emergencies.

Moving forward, EPA will continue to advance its climate adaptation efforts, and has reconvened the cross-EPA Adaptation Working Group in support of those efforts.

Human activity impacts our changing climate in some manner. The ability to measure with precision the degree and extent of that impact, and what to do about it, are subject to continuing debate and dialogue.

While there has been extensive research and a host of published reports on climate change, clear gaps remain including our understanding of the role of human activity and what we can do about it.

As a key regulatory voice, it is important for the Agency to strive for a better understanding of these gaps given their potential significant influence on our country’s domestic economic viability

Administrator Pruitt encourages an open, transparent debate on climate science.

Best regards,

Joel
Joel D. Scheraga, Ph.D
Senior Advisor for Climate Adaptation
Office of Policy

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The Ballot is stronger than the Bullet — Abraham Lincoln

Tin soldiers N.R.A. comin’
right here in America
This winter I hear the drummin’
seventeen dead in Florida

Gotta get down to it
guns are cutting us down
shoulda been done long ago.
What if you knew her, and
found her dead on the ground?
How can you run when you know?

Tin soldiers N.R.A. comin’
right here in America
This winter I hear the drummin’
seventeen dead in Florida
twenty-six dead in Sandy Hook
nine dead in church in Charleston
twenty-six dead at church in Texas
thirteen dead in Columbine
fifty-eight dead in Las Vegas … how many more?