Feet Above Sea Level

Well, there is a mean sea level--which is to say that sea level is not a constant. For any particular location, mean sea level is determined by comparing mean high sea level and mean low sea level (i assume you are familiar with the concept of tides). Tides can vary dramatically, sometimes as much as 45 to 55 feet (a basin in Nova Scotia has ranges that wide). Spring tides (which have nothing to do with the season Spring) occur when the sun, the moon and the earth are aligned, and are much more dramatic than any other tides.

New York, for example, is quite "low" with respect to the ocean. In 2009-10, the coastal regions north of New York city experienced a rise of about five inches in the highest tide readings--referring to standard tides, not spring tides or storm surges. Superstorms such as Sandy can have an immense impact--subways and tunnels were flooded in New York during the storm surge. The New York state Department of Environmental Conservation states that mean sea level has risen along the New York coastline by about one foot since 1900. They also state that mean sea level will probably rise by about one and half feet to four feet by the end of this century--without reference to catastrophic events--and may rise as much as six feet.

I suggest that you do a web search for "mean sea level+name of your city." I'm not going to ask you to tell us where you live, and that method will give a good deal of ambiguous information. Tide levels change, and the mean sea level everywhere on the planet has changed due to atmospheric and oceanic warming.

If you live in Bangladesh, move, move right now. Your nation is doomed by the end of this century, and probably will be half-awash in the next 50 years.

Setanta-

Thank you.

I live in New York City. I think some parts of the City are higher than others. During Hurricane Sandy I was told that I was not in the "evacuation zone."

If the West Antarctic ice sheet separates from that continent, you're all f*cked. Move to the Catskills.

I'm in New Mexico at 5,300 feet. Should I move?

If you have a smart phone, there are apps that will use GPS to get your elevation. Most running apps will do it.

I can't say . . . i don't know your neighbors. The Greenland glaciers are melting, but so far, the water has stayed in melt lakes on the surface. The West Antarctic ice sheet is now known to be detaching, very slowly, from the continent. Low end estimates give it 50 years, high end estimates give it 150 years. It's an ice sheet larger than Texas, and about two miles thick. It is resting on a part of the continent which has been depressed below sea level by the weight of the ice. If it detaches, and slides out to see, most of that two miles of ice will sink until 90% of it is underwater. Without considering the amount of water which will be added when it melts, that would raise global sea levels by about two meters--somewhat more than six feet. The Greenland glaciers could add another two or three meters (they're all above sea level right nowJ). The most dire predictions of which i know see the level of the oceans rising 20 meters, or about 65 feet.

So, no, you're fine where you are right now.

Setanta-

Thank you.

I don't have a smart phone but I guess all of New York City is close to sea level.

But if I was in a city high above sea level, would I be safe? I would need goods and services from the rest of the U.S. that might be submerged. The dispossessed people might seize my land.

Well, i was joking with the remark about the Catskills. Truly catastrophic consequences of global warming are fifty to a hundred years in the future. However, as Sandy showed, things can get bad in a hurry. I'd say you're safe for at least the next fifty years. If the city were permanently flooded in the low lying areas, you'd likely loose electricity, for a while at least, and maybe for quite a while. You probably would not have access to clean water and the sewer system would be trashed. A dramatic rise in sea levels would turn anywhere from 20% to 40% of the world's population into refugees, as well as flooding crucially important farm land. Your personal problems, while troubling to you, would be way down the list of important disasters.

what you ask for really isnt very easy to answer , heres a paper on predicting where flooding would occur based upon many factors
http://www.vims.edu/people/loftis_jd/CEUS_Prepared_Manuscript_Loftis_2014.pdf
I wouldnt get into the paper except for general information.
For your information I would call either the streets department or sewer and water department (NYC has its own EPA with engineers and GIS folks).
Id ask one of the engineers for mapping information that includes your building. They have all kinds of facilities maps in the GIS system and maybe they will let you look em over if it isnt part of a "Homeland Security" issue. (Lots of cities now have much stricter rules governing data access )

USGS produces topo maps that cover the city and these re updated evry 25 years or more frequently as projects warrant.

The ability to take that data and compute flood insurance information is a whole nother step. You can also get a copy of the FLOOD INSURANCE STUDY for NYC/NY . Thats done by FEMA usually under some contrqct to n gency or some engineering company. Id seen the flood insurance report for NYC a yer or so back so Im sure its on the net (google is our friend)

Most of these reports are blah blah bl;ah so have lots of coffee if you want to delve into finding the specific flood transect that includes your building (Knowing the map transect you live on is a big head start).

I think Georgeob's engineering company actually does these studies so he may have some way better data.

farmerman-

Thank you.

Theres a continentql glqcier with Fqrmington's number on it. Itll be winding up to get moving about 2850 AD. (lotta paperwork to take care of first)

You mean glaciers are aformin' because it's getting too warm? 2850AD means packing and moving time for me.

pretty much you should be outta there by then.
Youll thank me. .

Type in your address eg. Wall Street's elevation is supposedly 21 feet.

http://www.whatismyelevation.com/##

My house's elevation is 250 feet so I'm looking forward to being waterfront eventually unless the next ice age interferes with my property speculation.

If you're like me in New Mexico, you've got mile after mile of beautiful beach, and all you lack is a bit of water to make it into valuable sea shore.

I am amazed at how accurate that web site is. I put in some survey coordinates and got a number within a foot of the actual survey.

At least with a glacier, the furniture wont get all qet. Itll just get ground up into shavings

I would be a complete moraine to suggest that all Roger needs is more rain.

In this less than happy week, I decided to resurrect some silly threads from the "google Impaired" forum.

I think the OP actually meant this to be a serious subject, and, apart from Ms Toads excellent site wherein rel information was found to be available as an app, I got a chuckle from the rest of us

Yes , it would be somewhat presumptuous to laugh at me, and less than elevating.