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Scientists Plot Sea Levels Using GPS Satellites (engadget.com)
A team from the UK's National Oceanography Centre (NOC), University of Michigan and NASA's Jet Propulsion Laboratory have discovered a new way to accurately measure the sea level. The technique is called GNSS-R, and involves bouncing low-powered signals from GPS satellites off of the ocean's surface and measuring the reflected signal with a GNSS-R receiver. The team used a research satellite launched last year as a GNSS-R receiver, but it will be able to tap a new constellation of receivers that NASA is launching this year as part of CYGNSS. That mission will make accurate measurements of surface winds using GPS satellites, but NOC scientists will be able to use them to measure ocean levels, too, yielding a thirty-fold increase in such data.
It will turn us into a bunch of hypochondriacs with every little fluctuation
“He’s not deformed, he’s just drunk!”
Oregon State University ( http://www-po.coas.oregonstate... ? has been recording ocean s"sea level" and other data with sophisicated instruments since the 1970's.
This is an interesting leverage of GPS technology, but the data is for the most part already being collected in much finer detail with many additional parameters.
If you want news from today, you have to come back tomorrow.
When the satellites show that the sea level isn't rising, will you global warming supporters finally admit to being wrong? Or will you still demand more evidence?
could the under be covered?
... when these measurements corroborate the existing (and already very convincing) evidence for sea level rise, the wingnuts will come up with yet another obscure rationalization explaining why they should be discarded or ignored.
Alas, with deniers, it's like playing whack-a-mole: when you point to any specific piece of evidence, then out come the excuses for why that one thing is not relevant. When you point out the totality of evidence, out come the irrelevant details.
No, it means soon we'll have more data, which is always a good thing.
"First they came for the slanderers and i said nothing."
for a party that will pass unconstitutional laws requiring ID to vote on the mere thought that someone MIGHT commit voter fraud despite a lack of any evidence...it's sort of amusing to see the cries of there isn't enough data to prove AGW is happening so we shouldn't bother with it.
People in cars cause accidents....accidents in cars cause people
The more evidence we can gather about climate change, the better we can prove the tragedy to everyone in the world.
Of note, the use of GPS for surveying sea surface height has proposed or experimented with for a number of years (Cardellach, Estel; Martin-Neira, Manuel., April 2010). It might be because they've moved beyond 'proof of concept', but I think to say they discovered it is a bit strong. I've even found papers detailing the experimental use of GPS satellites to determine sea surface heights as far back as 2001 (Martin-Neira, M; Caparrini, M; Font-Rossello, J; Lannelongue, S; Vallmitjana, C S, 2001). The bggest change might be a reduction of errors, going from (30cm errors in 2000 to 5 - 15cm in 2009. If they've managed to further reduce the size of the errors then they're onto something really big. If they've just found a more efficient method of measuring sea surface heights in the open ocean, well that's pretty cool, but I'm not sure it's quite a game breaker.
As far as sea surface rise being a hoax, that's a silly statement, after all the empirical evidence is pretty strong, We have long term gauges that have been operating for centuries in a number of areas, and excepting for regions of crustal rebound, raw sea level rise is consistent with expectations if additional heat was being pumped into and inceasing the depth of the thermocline..
"The bass, the rock, the mic, the treble. I like my coffee black, just like my metal" - Mindless Self Indulgence
For the last 10 years wuwt has been trying to convince people of an international conspiracy of climatologists. It's soooo funny.
Oregon State University ( http://www-po.coas.oregonstate... ? has been recording ocean s"sea level" and other data with sophisicated instruments since the 1970's.
Interesting link, but nowhere on that page is there any mention of global measurements of sea level.
Because the raw data doesn't show a rise, and some people might misinterpret that.
More data is indeed good, but expect it to simply show more detail over the data we already have. It's highly unlikely that it would indicate anything substantially different at this stage to what we're already seeing, as you seemed to think might happen in another comment.
If it actually did indicate something different, and it didn't turn out to be instrument error or a faulty assumption in how it worked, then we'd not only have to look for similar undetected errors in our many other (much more mature) instruments, but we'd also have to come up with novel and probably tortuous explanations as to why the sea level wouldn't rise despite clear thermal expansion and the many cubic kilometers of melting land ice around the world that we can also measure...
Why would anyone engrave "Elbereth"?
That made what happened in Nevada even more entertaining. It explains why the GOP might think there's rampant voter fraud...because they have the receipts to prove it.
https://news.vice.com/article/...
You are welcome on my lawn.
There are plenty of measurements of sea level rise. Trouble is, they are all different. There are hundreds of tidal gauges, some of which have centuries of data (most of them more like 50-100 years). Trouble is that since they are located at/near seashores they not well distributed across the planet. And many are in places where various forces are lifting/depressing the ground at rates comparable to sea level rise. There are also satellite altimeters that measure sea level with radar. They have some problems as well (e.g. variable ionospheric delays, orbital uncertainties equal to several years worth of sea level change, etc.). The IPCC assessment reports address all that. I'd suggest tackling the actual chapters on sea level rise, not the sea level rise information in other chapters. AR5 Chapter 13 is the most recent, but I find it difficult to follow. I think AR4 Chapter 5 is easier going, but maybe that's just me.
You can't see ANYTHING from a car, You've got to get out of the goddamned contraption and walk...Edward Abbey
Satellite altimeter radar measurements from TOPEX/Poseidon, Jason-1, and Jason-2 satellites have been measuring sea level rise for decades: http://www.star.nesdis.noaa.go...
Nevada was the GOP's show.
Play Command HQ online
Wow, Now the deniers interpret a site that says NOTHING AT ALL as signs that the data agree with them.
That was my point. I must not have made it clear enough.
You are welcome on my lawn.
Graph 1
Graph 2
You will note Graph 1 is from the internet wayback archives, Graph 2 is the current one from NASA's website. They changed the data and made older temperatures colder and newer ones warmer.
No editorial, just the outright facts.
Is " game breaker" a new paradigm or an accidental mixed metaphor? Ha! capcha quibble!
That made what happened in Nevada even more entertaining. It explains why the GOP might think there's rampant voter fraud...because they have the receipts to prove it.
Just like how we knew that Saddam used to have WMDs, and that they were old as shit and basically expired.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Where, rather than accept the evidence we have so far, the idiots and fuckwits will insist that we don't have enough measurements to "prove" AGW is a problem, so we just have to make even MORE measurements.
Then YOU come along and whine about how there are too many measurements...
... when these measurements corroborate the existing (and already very convincing) evidence for sea level rise, the wingnuts will come up with yet another obscure rationalization explaining why they should be discarded or ignored.
You are referring to either the left or right lobe of a wingnut, or the whole thing? Wingnuts are the cutest little darlings. Unlike most nuts with their grasping-sides that rest quietly within a circular area, wingnuts seem to always be begging for attention. "Hey! Look at me!" they cry, their lobes rising like the arms of a child who wants to be picked up. They crave contact with forefingers and thumbs. There is nothing so sad as a wingnut that has never been adjusted. Every time I catch a glimpse of a wingnut that is in a dim recess of something, impossible to reach, I shed a tear for it. Regular nuts are like cats, one glance and you know you'll need special tools to deal with them and even those might not work. Wingnuts are more like dogs, playful, emotional and needy.
Pejorative political slang is become a freak show of Wingnuts versus Moonbats. which both have a pair of wings. Are both of these wings on the same side, like a flounder's eyes? I suppose there is an alternative Universe with left-wingnuts and rightwing-moonbats, blue-dog neocoons all watched over by a Moral Minority.
It's neat but this technique does not seem very wingnut-friendly because, accuracy, er, what. TA seems to have been carefully scrubbed of any indication of the degree of accuracy and that ambiguous "30-fold increase in such data" seems almost calculated to imply greater accuracy or global coverage over existing methods. I suspect they just mean oftener or morer.
<blink>down the rabbit hole</blink>
Personally, I was briefly involved in GNSS-R work in 2006. The article summary is quite inaccurate -to put it mildly- in claiming that this technique, GNSS-R, has just now been "discovered". The real news in this article is that big developments w.r.t. this *old* concept are still ongoing, which is good to hear.
Papers by e.g. ESA on this concept date back to at least 1993. Of course, thinking of an application is not quite the same as implementing it with a constellation of satellites, but still...
For those interested in some of the previous milestone dates, I'll just quote from the introduction of this 2002 paper (paywalled): ...
"The possibility of using reflected GPS signals for remote sensing was proposed [Martín-Neira, 1993], and fixed-platform experiments demonstrating GPS-reflection altimetry have been performed 20 m over the ocean [Anderson, 1996] [Martín-Neira et al., 2001], 450 m above Crater Lake [Treuhaft et al., 2001], and 10 m over a pond [Martín-Neira et al., 2002]. Global GPS altimetry would involve an orbiting receiver that obtains position and timing information from the GPS constellation as usual, but measures ocean height using the arrival time of GPS signals reflected from the surface.
The first space-based GPS reflection measurement [Lowe et al., 2002a] used SIR-C data collected on the Space Shuttle to create a preliminary link budget, and a number of Earth-grazing detections have been observed in Champ occultation data [Beyerle and Hoche, 2001] [Beyerle et al., 2002]."
Is it rise, or subduction?
Everybody knows that the elevation term of GPS solutions is the least precise of the three.