Rayong oil spill: Satellite photo shows oil cleared so far

[Cuban]

Tomorrow it will be 100% clean and the area will be better than ever. Tourism at an all time high.

I heard that tourist numbers were increasing to see the efficient clean up operation in effect.

[Cuban]

I'm currently on samet, the beaches on the east coast appear unaffected, not noticed any oil and just been for a swim.

Sent from my HTC Desire sponsored by Thai Tourism Co. Ltd.

I got a great shot of you returning to the beach - maybe a new avatar picture for you?

Original quote rephrased.

Edited August 2, 2013 by Cuban

[jamhar]

Latest satellite image.

[jamhar]

If you take 50kl and you spread that out in a film level thickness, it can cover a huge area. so yep, i buy the 50kl estimate to a rough order.

but the film size may actually be less. If there any remote sensing guys out there please correct me.

You cant actually "see" the film from satellite. But you can see what the film does to other measurable factors.

I wont bore you with measurement details for remote sensing but i think this is just the Aug1 shot and only from Aug1. maybe water vapor affected wavelengths combined with IR. a better measurement would have been to subtract a "control" of this date with the Aug 1 shot. Then the oil slick would be the primary difference and should show up a bit more clearly.

but still seeing the differences from day to day. ie, the july29, july31 and aug1 shots clearly shows the slick moving and only hitting the northern side of the island and getting smaller.

Yes you can see the difference between the oil and the water in the radar image, the reflection is different, just as an optical reflection is "seen" by your eyes to be of different colours

The x-band radar signature is not affected by normal water vapour or IR, but can be affected by heavy cloud containing lots of ice particles, but that is not the case here.

There are also observations in the C-band from the canadian radarsat-2 satellite which are even less effected and they also show the extent of the slick

The X-band Cosmo-skymed has been more usefuk in this case as it is a constellation of 4 satellites and so there is a greater frequency of imaging,

Interesting.

I've been out of Remote Sensing for a while and hadnt seen the recent research. I would have never thought about using sea surface SAR imagery for this purpose.

If you want to identify oil spills immediately you need to monitor enormous areas 24-7. The best view is from up in space.

Earth observation satellites such as TerraSAR-X og Radarsat-2 fire pulses of radar at the sea. These pulses are reflected back up to the satellite as echoes.

Oil on a rough sea

The amount of echo that returns tells a lot about the ocean surface. Small waves deflect radar pulses in all directions, including back at the satellite. With radar vision, this makes the sea look bright.

Oil spills cushion small waves. There’s even an expression for calming a situation down: “Pouring oil on troubled waters”.

The diffusion of the echo is narrower when the sea is calmer, making the surface of the sea act more like a mirror. Most of the radar waves bounce one way, away from the satellite. With radar vision the echo from a calm sea appears darker.

Example

"Satellite radar imagery showing an echo from three different types of oil slicks: A spill consisting of plant oil (top left), an emulsion of water and organic oil (center) and crude oil slick (bottom). The image was captured during an oil spill containment drill in the North Sea. (Image: RADARSAT-2 Data and Products © MacDONALD, DETTWILER AND ASSOCIATES LTD. (2011) − All Rights Reserved. The picture was delivered by KSAT, Tromsø)"

using polarized light it may be able to distinguish between grades of oil spill

This satellite radar image shows an echo as seen with 90-degree polarisation, taken during the clean-up drill in the North Sea. Again at the top left is a slick of plant oil, at the centre is an oil and water emulsion and at the bottom right is a slick consisting of petroleum. Note the three small red dots, which are ships with trailing wakes. (Image: RADARSAT-2 Data and Products © MacDONALD, DETTWILER AND ASSOCIATES LTD. (2011) − All Rights Reserved. The image was delivered by KSAT, Tromsø)

Personally i would have done it this was as noted below.

Giulio Ceriola · Planetek

Theoretically TIR sensors should be usefull, since the oil slick and the surrounding sea water would have different temperature. This difference would be the maximum when the slick occurr and then decreasing with time, but still existing since the different heating power in respect to the solar thermal irradiation. However I am not sure that this will result in a temperature difference easily appreciable from remote sensing.

Concerning the estimation of the oil slick thinkess, I see a possible scenarion (even if I didn't found any in literature).

1) The oil slick is detected by e.g. SAR technique

2) Using two TIR bands you can calculate the SST from the sea water and for the oil slick. To do so you have to consider that the oil slick has a different emissivity from the sea water, to be kept in account if you e.g. apply a Split Window algorithm

3) You should perform point 1) and 2) at least 2 times

4) You then can calculate the heating power of oil slick vs sea water

5) Theoretically you can link this difference to the thickness of the oil slick

As I said it is a possible scenario, with some difficulties.

But i disagree about the temp difference due to heating difference. I think the primary thermal difference will be due to the lack of evaporative surface cooling due to the presence of the oily film........

I broke my rule about not boring you with the details

I'll get my geeky butt under the rock that i crawled out from.

[jamhar]

I'm currently on samet, the beaches on the east coast appear unaffected, not noticed any oil and just been for a swim.

Sent from my HTC Desire sponsored by Thai Tourism Co. Ltd.

I got a great shot of you returning to the beach - maybe a new avatar picture for you?

Original quote rephrased.

just a hunch,

But i would say this is a bad time to light up a smoke.

[GeorgeO]

Got to remember what you are seeing in that photo is only a light sheen of oil not the thick sludge that entered the bay.

If you compare it with the previous day you will see it is smaller and more broken, it will probably disappear in the next few days

It won't disappear, it will just spread out enough so it cannot be viewed from space. Also, what won't be seen is all the damage to the ecosystem, sea creatures, plant life,and the effects of the spill on the health of all the people who live in the area. I am sure that the officials involved (PTT, TAT, etc.) will use those photos to try and dupe the public into believing that all is well and there is absolutely no danger to anyone in area. Perhaps hiring an independent outsider to evaluate the damage would give more credibility to any report about the safety. After all, Thailand always values and accepts outside expertise (Tongue in cheek here).

They're already spinning the images for their own ends. According to the latest statement, the clean-up is 90% complete ... yeah right...!

[jaffacake32]

Haha thanks Cuban, it does wonders for the skin!

Sent from my HTC Desire using Thaivisa Connect App

[ABCer]

Only 50,000 litres? I find that hard to believe.

An Olympic size swimming pool holds 2,500,000 litres... that's 50 times as much as the oil that was allegedly leaked.

50,000 litres wouldn't fill the pool in my garden. Doesn't sound right does it?

go and take one drop of used dirty engine oil and drop it in your swimming pool and come back and tell us how far it spreads out on the water....50k liters would cause a very big "slick"

The number could be right or it could be more, as we know from the GOM BP thing, companies will apply very conservative estimates over how much has leaked

"Oils ain't oils"! Engine oil, even used, cannot be compared with crude oil. Crude contains a lot of things. Tar is also a part of it. And some tars have negative to zero buoyancy. "Heavy" oil in salt water will coagulate into little balls of oil mixed with tar. Some will sink to the bottom. Some will still float. Some will swim in water. The only beneficiary will be PTTGC - out of sight, out of mind... But it will be only out of stupid minds. Because this is the beginning not the end of story...