[Coral-List] sea level rise speeding up

[Richard Dunne]

To further illustrate the concerns I raised below, a recent paper 
discusses the problems in using AVHRR SST data near to coastlines (a 
scenario which directly concerns those working on many coral reefs).

Brewin et al. Evaluating operational AVHRR sea surface temperature data 
at the coastline using surfers, Estuarine, Coastal and Shelf Science, 
Volume 196, 5 September 2017, Pages 276-289, ISSN 0272-7714, 
https://doi.org/10.1016/j.ecss.2017.07.011.
(http://www.sciencedirect.com/science/article/pii/S027277141730313X)

This is what they found:

"At the coastline we observe a significant degradation in the 
performance of AVHRR at retrieving SST ..... , with significantly higher 
root mean square errors ......  in the range of 1.0 to 2.0 °C. This 
clearly limits the use of AVHRR SST data at the coastline for 
applications that require errors to be less than that in this range. 
This finding is consistent with that of Smit et al. (2013), who caution 
against the use of 4 km SST MODIS Terra and Pathfinder v5.2 products 
around the coastline of South Africa, and observed significant biases 
between the satellite and in situ datasets. .................  for the 
majority of applications where error requirements in SST are lower than 
1.0 °C, there needs to be a significant improvement in the satellite 
AVHRR SST processing systems at the coastline."


Richard P Dunne

On 20/07/2017 15:18, Richard Dunne wrote:
> I have used satellite (SST & SSH), tide-gauge data, and GPS products for
> many years.
>
> Satellite data in particular is dependent on accurate calibration, and
> the quality of the processing algorithms (scientific guesswork?). When
> that earlier processing is shown to be wrong such as in this case it is
> not very reassuring.
>
> More generally, I have experienced Hadley SST products with inexplicable
> discrepancies, GPS data which has shown land rising, falling and
> stationary depending on which 'solution' is employed, and even
> tide-gauge data held on central databases with unexplained errors.
>
> Perhaps we are 'improving' in all this data collection and analysis. I
> hope so. In the meantime in trusting what is available it transpires
> that we are simply generating results that are rubbish. I guess it is
> time to start deleting some of the older (now inaccurate) papers - but
> which?
>
> Richard P Dunne
>
> On 19/07/2017 21:07, Douglas Fenner wrote:
>> Satellite snafu masked true sea-level rise for decades.
>>
>> http://www.nature.com/news/satellite-snafu-masked-true-sea-level-rise-for-decades-1.22312?WT.ec_id=NATURE-20170720&spMailingID=54526224&spUserID=MjA1NTA3MjA0OQS2&spJobID=1203043033&spReportId=MTIwMzA0MzAzMwS2
>>
>> Open-access.
>>
>> I note that they say that the new calculations fit with tide gauge records
>> around the world, all sources of info on sea level now agree.  I also note
>> that they report that average sea level rise around the world is now nearly
>> 4 mm per year.  Sea level rise is of course important for coral reefs.
>>
>> Cheers,  Doug
>>
>
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