Barrier Islands. Ocean City NJ's official height above sea level is
something like 36 inches. "A few feet" and they're gone.
Ocean Islands. Whole Pacific island populations are already having to
relocate and the handwriting is on the wall for others like the
nation of the Maldive Islands in the Indian Ocean.
U.S. Navy. I cannot cite, maybe somebody else can; but IIRC the Navy
is building something like 5 feet of sea level rise into it's plans over
the next so-many years - and I think the number is way less than 100.
On Saturday, April 4, 2015 at 10:23:10 AM UTC-4, bob haller wrote:
I look at NJ every day. Looking at it right now.
Nothing much new here, so far. We had serious
hurricanes here in the past. The first half of the last century
was a period of increased and more severe hurricanes. Last half,
1960s on, was more subdued, until Sandy. I've been saying for decades
that a big one was inevitable. Anyone with a lick of sense knew it.
We've had a huge influx of city folks move to the shore here in the last
two decades. People who have no concept of a hurricane, how destructive
they can be. They want to live on the water, so now they learned.
It's hard to tell me that the 6" rise in sea level over the last
100 years was a dominant or significant cause of what happened in NJ/NYC.
Then you have headlines like "most destructive hurricane ever.
Costliest hurricane ever." You think maybe the fact that there is 10X
the housing and commercial development here that there was in 1940 has
anything to do with that? Big, destructive storms have happened before.
They will happen again.
No offense but Sandy wasn't even a hurricane when it hit. It was just
a marginal CAT 1 but most reports had it as a tropical storm at
Perhaps the coastal communities will rebuild with a stricter building
code in the future and the next one will not be so devastating.
Two issues were apparent right away. Buildings were not at the FEMA
elevation and there seemed to be no regard for uplift loads. I know
when I was building in Maryland, all of the emphasis was on down
force. Nothing was ever strapped down to prevent things from going up.
They didn't even require nuts on the J bolts set in concrete support
It is not shocking that barrier islands are in danger, they are always
in danger. It was only in the last 50 years or so that people started
ignoring that fact.
That may not have been seen as true up north where hurricanes like
Sandy are once in a century events but it was well known down south
Beach buildings used to just be shacks that were expected to blow away
in a big storm and the whole concept of getting cheap government
backed insurance was not even considered.
The fact that some 3d world places are built in dangerous places does
not surprise me at all. Sea level rise is far from the most likely
danger to most of the people in danger
A lot is made about things the Pentagon "plans" on but they have to
have a plan for lots of things, most that are very unlikely to happen.
When you listen to the scientists who are not talking about very
unlikely circumstances, these sea rise projections ARE out 100 years
or more. We have plenty of things to worry about that are on far
shorter time scales. A world at war over water shortages is far more
likely than a rising ocean washing away coastal New Jersey.
In most cases, this is simply because we "made deserts bloom" with
massive, ill conceived 20th century water projects and mother nature
is striking back. We are seeing a lot of that in Florida too because
"draining the swamp" was seen as a great idea.
That's not really relevant, because it models only sea ice. You need to consider
-- Most of the Arctic ice cap is sea ice, floating on the surface of the ocean. Melting this ice
won't change sea level significantly, because it's displacing an equal mass of ocean water.
(There will be a slight increase because fresh water is less dense than salt water.)
-- Most of the Antarctic ice cap, and part of the Arctic ice cap (Greenland) is on land. Melting
this will cause sea level to rise, because it isn't displacing any ocean water now, and most
of it will wind up in the ocean. (Not all of it, because there's a substantial basin in the
Antarctic interior that will become a large freshwater lake if enough of the southern ice
-- Part of the Antarctic ice cap is resting on the continental shelf, *below* the surface of the
ocean. Melting this will cause sea level to *drop* because it's displacing an equal *volume*
of ocean water, not an equal mass.
So what happens to sea level if the polar ice caps begin to melt depends heavily on how
much of which ice cap liquifies.
here's a few more:
as the mass of the water held in ice at the south
pole decreases we get two additional effects, one is
that the overall ocean level increases for the northern
hemisphere increases not only from the amount of new
water added to the oceans but the rebound from the water
currently attracted to the gravity effect from that
much mass. the other effect is that as the cold water
warms up we also get an added boost in volume.
one thing i don't see anyone mention very often is
the amount of water that is being pumped from the
ground, used in sewage/water supply systems and then
dumped into the oceans. if we can reverse the trend
and impound more of this water in reservoirs and
ground water that can help slow down the rate of
ocean level increases.
where there are huge areas of inland seas below
sea level we could pipe sea water into them to help
moderate temperatures and evaporate more water into
the air to increase rainfalls/snowpacks downwind. this
would mean some plans for harvesting the salt from such
seas to keep them from getting too salty, but last i
knew there is a good market for sea salt... we do
really need a good plan to address the Salton Sea mess
as it goes, where one of my relatives is at he's lost
1ft of sea level and has only another foot and a half
before that is gone. another 20-30 years and it is
likely where he is at will be close to under water.
Yeah, the comment is a bit out of line isn't it.
We can only speculate why Rebel1 thought he knew better than
all the worlds scientists.
But then, Rebel1 claimed "there are good analytical minds here".
(Yes, I laughed so hard, I almost choked.)
Maybe it's not so out of line to guess he was referencing
those mass poster nut jobs that live in my kill file.
The idea that scientists are scammers making things up for profit
does seem to come from one political party.
But only Rebel1 can explain why he suddenly thought he was
smarter than a bunch of people that actually studied the subject.
I wonder if he actually performed his "tall glass" experiment.
I bet it was a tall jelly glass and a sharpie.
We all know calibrated beakers, are for pinko scientists.
Most of these folks see some headline written by a clueless
reporter (often from both sides of the debate) and elaborate
on that, rather than actually digging into the science itself.
There are several contributors to planetary mean sea level (MSL).
- Meltwater from land-based glacial ice
- Fossil water runoff
- Isostatic rebound
The first, meltwater from land-based glacial ice
encompasses the high altitude glaciers (e.g. in the
himalayas, upper Rockies, Peru, mt. Shasta, etc), the greenland
icecap and the antarctic icecap.
The second, fossil water runoff is from pumping
geologic water from underground for irrigation and
other human uses. This adds water to the hydrologic
cycle which raises sea level (in fact, this alone is
responsible for something like 40% of the sea level
rise in the 20th century).
The third, isostatic rebound, appears to lower sea
level at certain measuring stations as the land continues
to recover from the weight of a mile of ice 10kya.
A counterpoint of this is areas like southern La., where
the land is sinking due to silting at the mouth of
the mighty muddy.
The largest two regions of land-based ice are the
greenland icecap and the antarctica icecap. In both
cases, the amount of time required to melt 100% of the
ice is measured in thousands of years (note that the air
temperature in antarctica is below freezing for 10 months
of the year). Since the land ice in antarctica is surrounded
by sea ice (which can melt more rapidly as the temperature of
the water it is floating on changes with time, natural cycles
and other forcings), a concern is that if all the sea ice
melts, it will open the way for the land-based glaciers to
flow more rapidly towards the sea and calve bergs, which will
inevitably cause higher sea levels.
As for Wind, certain coastal areas measure higher sea
levels than others due to the wind pushing water towards
the coast (leaving aside any tidal effects).
All this makes it difficult to measure MSL accurately
using surface based measurements. Modern measurements
use satellite altimetry, which generally requires some
amount of correction due to orbital decay characteristics
and instrumental differences beween generations of
Current global sea ice area:
Current global sea ice anomoly (i.e. difference from average since 1979)
Global, Arctic and Antarctic ice area:
Note that the planet currently has _more_ sea ice than the
average since 1979 (when satellite measurements began). Note
also two years ago, when there was 2 million km2 less.
As others have pointed out, the melting of the sea ice has
effectively no effect on MSL; however it does alter the
albedo of the pole(s) which may reduce the amount of
insolation reflected back to space, leading to
additional warming of the surface water.
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.