Satellite technique could use internal tide data to track ocean temperature cheaply and without harming marine life, potentially improving climate modelling.
For scientists trying to monitor, model or predict climate change, accurate information about temperatures on the Earth are vital, and this just doesn’t just mean on the land’s surface; it means understanding how temperatures are changing throughout the atmosphere, and what happens to heat when it percolates through the various layers. One important factor is surprisingly hard to measure: how heat affects the sea.
It’s thought that a great deal of the heat that passes through the atmosphere, and which climatologists believe is trapped by greenhouse gases, ends up in the oceans. But the only part of the sea where temperature is easy to measure is the surface; figuring out temperatures in the depths is neither easy nor cheap, but because of the huge volume of water on the planet and the amount of heat that it can store, it’s very important for assessing the effect on the overall climate. Oceanographer Zhongxiang Zhao of the University of Washington has been studying the behaviour of the deep ocean and believes that he might have found a new method involving satellite data that is already available.
The only definite way of directly measuring deep ocean temperature is using floats that work at depth; these are expensive to maintain, however. Another way of indirect measurement is to measure the time that the acoustic pulse takes to traverse a set distance, as sound travels quicker in warmer water than cooler. But acoustic pulses can disorientate marine mammals, and use of this technique was halted in 2006.
Zhao’s technique uses a lesser-known behaviour seen in the oceans: internal tidal waves. Like the familiar surface tides, these are caused by the gravitational pull of the moon (and to a much lesser extent, that of the sun). Internal tidal waves are very much smaller than this, and Zhao explained that they tend to start at submarine ridges on the ocean’s bed, when tidally-driven currents are forced over them. They then travel with a wavelength of about 160km and a speed of 3 to 4m/sec. Climate change is warming the upper oceans more than the depths, and this increases the speed of the internal tidal waves.
Importantly, an internal tidal wave increases the height of the sea surface by about 2cm, even though the wave itself maybe 20 to 50m high. This is 50 times smaller than the height of the tide at the surface, but can still be detected by satellites tracking the ocean height. The complex behaviour of water waves makes this difficult, but Zhao has spent a decade working out how to differentiate these height changes due to internal tidal waves from other phenomena.
Zhao explainsedthat internal tidal waves along two particular paths a the Atlantic Ocean have increased by one per cent in the last 20 years; this corresponds to a temperature increase which was in agreement with one measured by the Argo oceanographic floats, which float 2km below the ocean surface. “This method offers a long-term, cost-effective, environmentally friendly technique for monitoring global ocean warming,” he said.
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So, apart from the “proven science” being totally flawed in the evaluation of radiation “fiddle factors” (otherwise known as RFFs) to get any warming, the climate “scientists” have now discovered that most of the world’s energy resides in the oceans! All they need is a few more billion in funds and all will be clear.
OMG does not describe the situation where the UK (and most of Europe) have sacrificed their energy futures / economies to the crazy “carbon dioxide is bad” lobby.
“Have now discovered” or, as should be said by those concerned with actually portraying reality rather than attempting to spin their own version of it, have known and repeatedly said for years, while also noting the difficulty of measuring it.
OMG hardly describes the continuing whingeing of global warming deniers.
“OMG hardly describes the continuing whingeing of global warming deniers.”
Global warming sceptics accept that the climate changes naturally. Global warming believers deny that it does so. Who then are the deniers?
The plain fact is that the world has not warmed as predicted for the last 18 years and temperatures have returned to a level consistent with this after the recent El Niño caused warming. So the real puzzle is to work out how extra heat got from an atmosphere that hadn’t warmed into the ocean. Seems like a miracle worker is needed.
“Global warming believers deny that it does so”
This statement is so far from the truth it could have come from the mouth of Donald Trump.
“The plain fact is that the world has not warmed as predicted for the last 18 years.”
This has been debunked throroughly, but is repeatedly trotted out by people who don’t keep an eye on the literature.
The intention, the descriptions, and just some of the abject failures of the GW alarmists:
“We have to offer up scary scenarios… each of us has to decide the right balance between being effective and being honest.” -Stephen Schneider, lead IPCC author, 1988
“Entire nations could be wiped off the face of the Earth by rising sea levels if the global warming trend is not reversed by the year 2000.” -Noel Brown, ex UNEP Director, 1989
“A billion people could die from global warming by 2020.” -John Holdren, Obama’s current Science Czar, 1986
“[Inaction will cause]… by the turn of the century [2000], an ecological catastrophe which will witness devastation as complete, as irreversible as any nuclear holocaust.” -Mustafa Tolba, 1982, former Executive Director of the United Nations Environment Program
“In twenty years (2008) the West Side Highway [and thus much of Manhattan] will be under water.” -James Hansen, 1988, NASA
On the other hand NASA tells us the planet is in rude health with 14% more greening thanks to increased atmospheric CO2. https://www.nasa.gov/feature/goddard/2016/carbon-dioxide-fertilization-greening-earth/
The alarmists didn’t see that coming……another fail.
The first statement is one that any doctor would agree with. The second doesn’t specify when the nations could be wiped off the Earth, so could still be true. It’s 2016, so the third could still be true also. The fourth doesn’t specify when the devastation would happen. The fifth has been proved false. But climate scientists certainly did see more greening coming in the short term.
Amazing what happens when you actually read the quotes!
This just seems to confirm that we have a very limited idea as to what is going on in terms of global temperatures and various gas concentrations. To have leapt to ludicrous and economically crippling measures allegedly to limit CO2 without a substantive, impartial, objective and independent evidence base just demonstrates how gullible politicians and the media have become.