NOAA establishes 'tipping points' for sea level rise related flooding

NOAA establishes 'tipping points' for sea level rise related flooding
Annapolis, Maryland, pictured here in 2012, is one of three major East Coast urban areas already being faced with nuisance flooding in excess of 30 days per year. Credit: With permission from Amy McGovern

By 2050, a majority of U.S. coastal areas are likely to be threatened by 30 or more days of flooding each year due to dramatically accelerating impacts from sea level rise, according to a new NOAA study, published today in the American Geophysical Union's online peer-reviewed journal Earth's Future.

The findings appear in the paper From the Extreme to the Mean: Acceleration and Tipping Points for Coastal Inundation due to Sea Level Rise, and follows the earlier study, Sea Level Rise and Nuisance Flood Frequency Changes around the United States, by the report's co-author, William Sweet, Ph.D., oceanographer at NOAA's Center for Operational Oceanographic Products and Services (CO-OPS). The new analysis was presented at a news conference today at the annual AGU fall meeting in San Francisco.

NOAA scientists Sweet and Joseph Park established a frequency-based benchmark for what they call "tipping points," when so-called nuisance flooding, defined by NOAA's National Weather Service as between one to two feet above local high tide, occurs more than 30 or more times a year.

Based on that standard, the NOAA team found that these tipping points will be met or exceeded by 2050 at most of the U.S. coastal areas studied, regardless of likely to occur this century. In their study, Sweet and Park used a 1½ to 4 foot set of recent projections for global sea level rise by year 2100 similar to the rise projections of the Intergovernmental Panel for Climate Change, but also accounting for local factors such as the settlement of land, known as subsidence.

These regional tipping points will be surpassed in the coming decades in areas with more frequent storms, the report said. These will be also be exceeded in areas where local sea levels rise more than the global projection of one and half to four feet. This also includes coastal areas like Louisiana where subsidence, which is not a result of by climate change, is causing land to sink below sea level.

NOAA establishes 'tipping points' for sea level rise related flooding
This chart shows that most major US coastal cities will pass 30-days of nuisance flooding by 2050. Credit: NOAA/Earth's Future

NOAA tide gauges show the annual rate of daily floods reaching these levels has drastically increased - and are now five to ten times more likely today than they were 50 years ago.

"Coastal communities are beginning to experience sunny-day nuisance or urban flooding, much more so than in decades past," said Sweet. "This is due to sea level rise. Unfortunately, once impacts are noticed, they will become commonplace rather quickly. We find that in 30 to 40 years, even modest projections of rise—1½ feet by the year 2100—will increase instances of daily high tide flooding to a point requiring an active, and potentially costly response and by the end of this century, our projections show that there will be near-daily nuisance flooding in most of the locations that we reviewed."

"As communities across the country become increasingly vulnerable to water inundation and flooding, effective risk management is going to become more heavily reliant on environmental data and analysis," said Holly Bamford, Ph.D., NOAA acting assistant secretary for conservation and management. "Businesses, coastal managers, federal, state, and local governments, and non-governmental organizations can use research such as this as another tool as they develop plans to reduce vulnerabilities, adapt to change, and ensure they're resilient against future events."

"The importance of this research is that it draws attention to the largely neglected part of the frequency of these events. This frequency distribution includes a hazard level referred to as 'nuisance': occasionally costly to clean up, but never catastrophic or perhaps newsworthy," said Earth's Future editor Michael Ellis in accepting the paper for the online journal.

Ellis also observed that "the authors use observational data to drive home the important point that nuisance floods (from inundating seas) will cross a tipping point over the next several decades and significantly earlier than the 2100 date that is generally regarded as a target date for damaging levels of . The paper also raises the interesting question of what frequency of 'nuisance' corresponds to a perception of 'this is no longer a nuisance but a serious hazard due to its rapidly growing and cumulative impacts'."

The scientists base the projections on NOAA tidal stations where there is a 50-year or greater continuous record. The study does not include the Miami area, as the NOAA tide stations in the area were destroyed by Hurricane Andrew in 1992 and a continuous 50-year data set for the area does not exist.

Based on that criteria, the NOAA team is projecting that Boston; New York City; Philadelphia; Baltimore; Washington, D.C.; Norfolk, Virginia; and Wilmington, North Carolina; all along the Mid-Atlantic coast, will soon make, or are already being forced to make, decisions on how to mitigate these nuisance floods earlier than planned. In the Gulf, NOAA forecasts earlier than anticipated floods for Galveston Bay and Port Isabel, Texas. Along the Pacific coast the earlier impacts will be most visible in the San Diego/La Jolla and San Francisco Bay areas.

Mitigation decisions could range from retreating further inland to coastal fortification or to a combination of "green" infrastructure using both natural resources such as dunes and wetland, along with "gray" man-made infrastructure such as sea walls and redesigned storm water systems.

NOAA's mission is to understand and predict changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and to conserve and manage our coastal and marine resources. Join us on Twitter, Facebook, Instagram, and our other social media channels.


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NOAA: 'Nuisance flooding' an increasing problem as coastal sea levels rise

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Dec 29, 2014
One of the Carolinas declared seal level change to be illegal, . . . just before a report was issued by their own professional state environmentalists showing they were subsiding at one of the highest rates in the nation.

Dec 29, 2014
This is nothing but AGWite scaremongering. The whole, "The sea levels are catastrophically rising!" hysteria has been a lie, all along.

http://nzclimates...levl.pdf


Dec 30, 2014
This is nothing but AGWite scaremongering. The whole, "The sea levels are catastrophically rising!" hysteria has been a lie, all along.

http://nzclimates...levl.pdf



So, here is Uba's attempt to sneak in a contrarian paper that is published in a "journal" that was founded to disprove plate tectonics.

http://www.ncgt.org/

I have to admit this is lower quality than even Uba usually presents.

Dec 30, 2014
I have to admit this is lower quality than even Uba usually presents.
@Thermo
i am not so sure... i think uba is getting frustrated with the site and the fact that she can't actually support her contentions with science

Her recent behaviour has demonstrated the desperation of her anti-science "cause"

I've noticed that she has never once refuted the science studies i linked to the site (these: http://www.scienc...abstract and this one http://marine.rut..._pub.pdf )

Those were chosen specifically to refute her points in other threads but there was never a refute, equivalent evidence or even an attempt to reply with anything resembling science regarding those studies

Maybe we will see some actual science, but given the above demonstration, this is doubtful

Dec 30, 2014
HEY UBA
i am not so sure... i think uba is getting frustrated with the site and the fact that she can't actually support her contentions with science
i noticed you downvoted the comment

that is your prerogative... but I still gotta ask:

WHERE are the papers or equivalent reputable evidence that refutes the science in the links above?

you are continually going on about how AGW cannot be real, arguing semantics and definitions and cherry picking data to support your conclusions

Now is your chance to shine and prove to the world that AGW isn't real... and all you do is downvote and TROLL post

you even posted a link on another thread with polar bears and penguins together, which is stupid at best!

where is the science refuting the studies i asked for?
i kept it simple and used two studies that directly refuted your comments and assertions and you are STILL ignoring them

Why?

Dec 30, 2014
This is nothing but AGWite scaremongering. The whole, "The sea levels are catastrophically rising!" hysteria has been a lie, all along.

http://nzclimates...levl.pdf
So, here is Uba's attempt to sneak in a contrarian paper that is published in a "journal" that was founded to disprove plate tectonics.

http://www.ncgt.org/

I have to admit this is lower quality than even Uba usually presents.
The accepting journal is irrelevant. Do you have a problem with the methodology?


Dec 30, 2014
HEY CAP'N
I've noticed that she has never once refuted the science studies i linked to the site (these: http://www.scienc...abstract )

Those were chosen specifically to refute her points in other threads but there was never a refute, equivalent evidence or even an attempt to reply with anything resembling science regarding those studies
Lying doesn't become you. Or is it that you are a chatterbot and therefore have no recollection of the discussion?

Dec 30, 2014
HEY CAP'N
WHERE are the papers or equivalent reputable evidence that refutes the science in the links above?
Where is your acceptance of the standard definition for global warming? How can we even discuss a subject to which we don't even agree on a definition?

you are continually going on about how AGW cannot be real, arguing semantics and definitions and cherry picking data to support your conclusions
Nope, just standard definitions and empirical data suffices.

you even posted a link on another thread with polar bears and penguins together, which is stupid at best!
LOL. I was surprised you noticed.

where is the science refuting the studies i asked for?
i kept it simple and used two studies that directly refuted your comments and assertions and you are STILL ignoring them

Why?
Why did you ignore my response?


Dec 30, 2014
The accepting journal is irrelevant. Do you have a problem with the methodology?

It's an odd article, to be sure. Using words like "rubbish" in the article indicate the author isn't really good at calmly evaluating evidence. His use of Fig. 3 (Fig. 13 from the original article from the Australian BOM) is a good example. His Fig. 3 is a display of sea level rise. Each square represents 25mm/year. Anything other than 0 means an unstable sea level so the graph shows that sea levels are rising, contrary to the title of his article. The fact that he doesn't seem to realize what the graph represents says a lot about the author. You've linked to a self-refuting article. Why didn't you read it before linking to it?

Dec 30, 2014
The accepting journal is irrelevant. Do you have a problem with the methodology?

It's an odd article, to be sure. Using words like "rubbish" in the article indicate the author isn't really good at calmly evaluating evidence. His use of Fig. 3 (Fig. 13 from the original article from the Australian BOM) is a good example. His Fig. 3 is a display of sea level rise. Each square represents 25mm/year. Anything other than 0 means an unstable sea level so the graph shows that sea levels are rising, contrary to the title of his article. The fact that he doesn't seem to realize what the graph represents says a lot about the author. You've linked to a self-refuting article. Why didn't you read it before linking to it?
Did you not notice the claim, "...since about 2001 there has been no significant
change in sea level for any of the islands studied, including Tuvalu."

Maybe you should examine the article and the graph more carefully before spouting off.


Dec 30, 2014
Did you not notice the claim, "...since about 2001 there has been no significant
change in sea level for any of the islands studied, including Tuvalu."

Note the full quote: "The results are shown in Figure 3. The level was disturbed near the beginning because of the effects of ENSO (El niňo-Southern Oscillation, often simplified to El niňo), but since about 2001 there has been no significant change in sea level for any of the islands studied, including Tuvalu."
He got his "no significant change" from Fig. 3. Yet Fig. 3 shows a clear sea level rise of ~5mm/year. So either he doesn't understand his Fig. 3, or he's just making things up. Again, Fig. 3 looks at sea level rise. Anything other than 0 means the sea level is changing. The title of the graph (Sea Level Trends, with units of mm/year) should be a giveaway. It's a very embarrassing (or, perhaps, telling) mistake on his part.

Dec 30, 2014
At the risk of overexplaining things, I'll be a bit more explicit. The author of your article (and I'm guessing you, as well) seem to believe that his Fig. 3 shows the sea level at various places. It does not. It shows the annual change in sea level at those places. If, and only if, the value in the figure is 0, then the sea level isn't changing. Whenever the values in the figure do not equal 0, then the sea level is changing - rising for positive values and falling for negative values. Every location plotting on the figure shows rising sea levels, according to the figure presented by your author. This doesn't represent a stable sea level, so the figure refutes the contents of the article.

Dec 31, 2014
He got his "no significant change" from Fig. 3. Yet Fig. 3 shows a clear sea level rise of ~5mm/year.
Not "since 2001." In fact, most show a decrease in sea level since that date.

So either he doesn't understand his Fig. 3, or he's just making things up.
Or you just don't understand the phrase, "since 2001."

Again, Fig. 3 looks at sea level rise. Anything other than 0 means the sea level is changing. The title of the graph (Sea Level Trends, with units of mm/year) should be a giveaway. It's a very embarrassing (or, perhaps, telling) mistake on his part.
No, the mistake is clearly yours.


Dec 31, 2014
At the risk of overexplaining things, I'll be a bit more explicit. The author of your article (and I'm guessing you, as well) seem to believe that his Fig. 3 shows the sea level at various places. It does not. It shows the annual change in sea level at those places.
No, it shows "Sea Level Trends Through Septeber 2008." It says nothing about annual changes in sea level. And with your interpretation, you would have to explain the HUGE sea level swings from 1993 to 2000.

If, and only if, the value in the figure is 0, then the sea level isn't changing. Whenever the values in the figure do not equal 0, then the sea level is changing - rising for positive values and falling for negative values. Every location plotting on the figure shows rising sea levels, according to the figure presented by your author. This doesn't represent a stable sea level, so the figure refutes the contents of the article.
Wow, is this really what you see here? Where did you get this?

cont

Dec 31, 2014
At the risk of overexplaining things, I'll be a bit more explicit. The author of your article (and I'm guessing you, as well) seem to believe that his Fig. 3 shows the sea level at various places. It does not. It shows the annual change in sea level at those places.
No, it shows "Sea Level Trends Through Septeber 2008." It says nothing about annual changes in sea level.

What did you think "trends" meant? Look at the paper he got the figure from (http://www.bom.go...0809.pdf ). Look at the first table and the column labeled "Trend (mm/yr)". It's telling how the sea level is currently changing. Or look at the discussion of Figure 13 (where your author got his Figure 3) on page 8. Seriously, if you can't understand this fairly simple figure, I'm not sure how else I can help you.

Dec 31, 2014
From the original paper regarding this graph:

"Sea Level Trends

"The evolution of the monthly trend values (in mm per year) at each station from one year after installation to present is depicted in Figure 13. This figure illustrates that as the sea level record becomes longer, the relative sea level trend estimates become more stable and reliable."

So, it shows the trends have generally diminished to near zero over time. The two graphs above it (11 and 12) also support the claim "...since about 2001 there has been no significant change in sea level for any of the islands studied, including Tuvalu."

I think you are missing the word, 'significant."

Remember, the AGWite claim is these islands are sinking rapidly.

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