Human impacts of rising oceans will extend well beyond coasts

May 27, 2011, University of Wisconsin-Madison

Identifying the human impact of rising sea levels is far more complex than just looking at coastal cities on a map.

Rather, estimates that are based on current, static can greatly misrepresent the true extent – and the pronounced variability – of the human toll of climate change, say University of Wisconsin-Madison researchers.

"Not all places and not all people in those places will be impacted equally," says Katherine Curtis, an assistant professor of community and environmental sociology at UW-Madison.

In a new online report, which will publish in an upcoming issue of the peer-reviewed journal Population and Environment, Curtis and her colleague Annemarie Schneider examine the impacts of rising oceans as one element of how a changing climate will affect humans. "We're linking economic and social vulnerability with environmental vulnerability to better understand which areas and their populations are most vulnerable," Curtis says.

They used existing climate projections and maps to identify areas at risk of inundation from rising sea levels and storm surges, such as the one that breached New Orleans levees after Hurricane Katrina, then coupled those vulnerability assessments with projections for future populations.

It's a deceptively challenging process, the authors say. "Time scales for climate models and time scales for human demography are completely different," explains Schneider, part of the Center for Sustainability and the Global Environment at UW-Madison's Nelson Institute for Environmental Studies. "Future climate scenarios typically span 50 to 100 years or more. That's unreasonable for demographic projections, which are often conducted on the order of decades."

The current study works to better align population and climate data in both space and time, allowing the researchers to describe social and demographic dimensions of environmental vulnerability.

The analysis focuses on four regions they identified as highly susceptible to flooding: the tip of the Florida peninsula, coastal South Carolina, the northern New Jersey coastline, and the greater Sacramento region of northern California, areas that span a range of population demographics. (New Orleans was not included as a study site due to major population changes since the 2000 census.)

With help from the UW-Madison Applied Population Laboratory, the researchers used 2000 census data and current patterns of population change to predict future population demographics in those areas. By 2030, they report, more than 19 million people will be affected by just in their four study areas.

And many of those people may be in unexpected places. The case studies clearly reveal the importance of considering people's patterns of movement.

"No area is completely isolated, and migration networks are one of the ways we think about connections across places. Through these networks, environmental impacts will have a ripple effect," Curtis says.

In one example, if Florida floods, New York and Los Angeles will feel the effects – in 2000, 14,000 people from three New York counties and another 5,500 from Los Angeles moved to Miami-Dade County, Fla. Under the environmental scenarios in the study, those people would have to remain where they started or move elsewhere, consequently shifting their resources and needs to new sites.

Curtis and Schneider designed their approach with an eye toward helping local authorities identify and best respond to their own needs.

"Adaptation and mitigation strategies are developed and implemented at a local level. Part of the problem with large-scale population and environmental impact estimates is that they mask the local variation that is necessary in order for a local area to effectively respond," Curtis says.

A population's demographic, social, and economic profile affects the ways in which people can respond to local disaster, she adds. For example, children or elderly require a different approach to evacuation and resettlement than a largely working-age population, while workers from the agricultural lands of northern California will face different post-displacement labor challenges than those from the industrial corridor of New Jersey.

Even using rough estimates of sea level rise, their analysis makes clear that planning ahead for mitigation and adaptation will be crucial, Schneider says.

"As we anticipate future events, future natural disasters, we've learned how dramatic it can be – and there are things that can be done in advance to mitigate the extent of damage in a location," Curtis says.

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2.8 / 5 (13) May 27, 2011
problem is that there hasnt been a rise.

this is kind of like doing the science of maybes...
as if "what if" comix were real
3.2 / 5 (9) May 27, 2011
@ArtflDgr, is that why the Dutch have invested a lot of resources into their dams more than once? The Netherlands is 7 feet below sea surface.

Give me evidence that it is not rising.
4.1 / 5 (9) May 27, 2011
The average rise of the sea level for the last 10,000 years is 3 feet. The predicted rise for the next century is...3 feet. See a pattern here? Major Archaeology is being done at 200-300 feet below sea level on the continental shelf because that used to be the shoreline!
5 / 5 (3) May 27, 2011
Sorry i said 7 feet but it is 7 meter. sorry about that.
Or was it 7 feet?? Agg its late, look it up on google i would say.
2 / 5 (12) May 27, 2011
problem is that there hasnt been a rise.

this is kind of like doing the science of maybes...
as if "what if" comix were real

Yes, it has become very fashionable and lucrative for climatologists to ignore the well-known, natural variability of Earth's heat source - the Sun [1,2].

1. "Super-fluidity in the solar interior: Implications for solar eruptions and climate",
Journal of Fusion Energy 21, 193-198 (2002)

2. "Earth's Heat Source - The Sun", Energy and Environment 20, 131-144 (2009)

With kind regards,
Oliver K. Manuel

3.3 / 5 (8) May 28, 2011
The Earth oscillates between Ice Ages and Tropical periods.
It has done so for at least millions of years and quite possibly billions of years.
We are in a warming period and have not as yet reached the peak of that warming period.
The question is not and should not be is our planet warming, (because it is warming as part of the planets natural cycle) but rather what influence, if any, are we having on this natural process.
We are not capable of stopping it but we may well be capable of accelerating it.
That is what we need to know.
And to what extent are we capable of accelerating it.
Plus if we contain our pollution will it have any detectable effect upon this natural cycle.
I suspect that the answer will be no.
That any acceleration we may have contributed to will remain as part of the cycle, i.e. we cannot extract it.
The best I think we can do is to not further add to the acceleration of the warming process.
3.7 / 5 (6) May 28, 2011
1.8 / 5 (5) May 29, 2011
Envisat suggests almost no rise since 2004.

5 / 5 (2) May 29, 2011
Envisat suggests almost no rise since 2004.


Looking at the link you provided shows 6 different measurements, one which doesn't agree. I can understand why you would cherry pick the one that disagrees, but don't you feel a little slimy about it? Normally, data is averaged together, and there is certainly a long term linear trend of sea level rises as shown by ShotmanMasio's links. Whats scary is that the measured rises are at the very top end of climate model projections.
1 / 5 (2) May 30, 2011
Some of those satellites are no longer functional.

Only 3 are functional today and all 3 show a drop.

Many scaremongers predict a 1 meter rise by 2100. That would require 10mm per year of sea level rise.

The average rise of 2.7mm is short 7.3mm per year and 73mm behind the needed pace to make 1 meter by 2100.

Of course now that sea level has dropped ... it is even farther behind.
2.3 / 5 (3) May 30, 2011
NotParker: I assume you will share your references with us. Please make sure they are from authoritative sources. It seems like you are just making up the idea that sea levels are trending lower. Note, I say "trending." I am sure you would not try to obfuscate the information by confusing a fluctuation with a trend. So, I will be waiting patiently to see your references.

For instance, you can see in this University of Colorado graph that the trend is rising even with fluctuations along the way.

Can you show me long-term trends that show this is wrong?

Or how about showing this one is wrong:


I will be waiting for your scholarly data to show that you are not just lying.
1 / 5 (1) May 30, 2011
The University of Colorada data shows a miniscule rise in the last 7 years.

Third measurement in 2004 - 2004.0630 27.604
Third measurement in 2011 - 2011.0673 30.809

3.2mm in 7 years.


That link is the Raw Data link on YOUR referenced page. Didn't you read it??????

To rise 1 meter (1000mm) in 100 years you need 10mm a year.

Not .45mm a year over the last 7 years.

I'm not lying. I actually looked at the data ... you should try it.
2.3 / 5 (3) May 30, 2011
Not Parker:

Absolutely shameless cherry picking. I am surprised you would even try this. Let me cherry pick:

2010.9587 38.030
2004.5789 17.311

The difference is now 20.719 mm in 6 years just by changing the dates slightly. That is the reason that they use averaging to eliminate the noise. At the present time the average by multiple sources is about 3.2 mm/year, not in 7 years.

Using your logic that would be about 320 mm over the next century. However, the is not taking into account that the increase is not expected to be linear. So, you are cherry picking data (as expected) and do not understand statistics (as expected). You also, apparently, don't understand the concept of feedback. I think you need to do a little more reading before you try to make this lie stick.

Please show an example to support your idea that sea level is not rising based on someones statistics and not your cherry picked instantaneous arithmetic.
1 / 5 (1) May 30, 2011
The last data for 2011 is the 3rd entry for the year.

I then went back and looked at the 3rd entry for 2004.

You have to compare the same time each year because of seasonal differences.

No cherry picking.

Why would you want to compare different months?

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