PhillipS Posted April 26, 2012 Share Posted April 26, 2012 We agree to disagree on the matter. I'm not sure what to believe and I feel that waiting for the info directly from the team is not unreasonable. But you've claimed that there are peer-reviewed papers on Cryosat and its accuracy already published - weren't you telling the truth? Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted April 26, 2012 Share Posted April 26, 2012 We agree to disagree on the matter. I'm not sure what to believe and I feel that waiting for the info directly from the team is not unreasonable. You know of countless validation papers from the team. So you should already know this. Fyi, volume = area x thickness or or Area = volume/thickness. If you can't use the volume and thickness the team gave us to piece it together your trolling us Link to comment Share on other sites More sharing options...
LithiaWx Posted April 26, 2012 Share Posted April 26, 2012 But you've claimed that there are peer-reviewed papers on Cryosat and its accuracy already published - weren't you telling the truth? I wasn't referring to accuracy. I was referring to the volume numbers in relation to PIOMAS. And yes there are peer reviewed papers that suggest Cryosat-2 is accurate and the biggest margin is like 20cm. They are out there and I've posted the links a few times already. I have never questioned the accuracy, others have. I've said all I have to say on the subject for the time being. Any other discussion at this point is going to lead to back and forth nastiness it appears. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted April 26, 2012 Share Posted April 26, 2012 I wasn't referring to accuracy. I was referring to the volume numbers in relation to PIOMAS. And yes there are peer reviewed papers that suggest Cryosat-2 is accurate and the biggest margin is like 20cm. They are out there and I've posted the links a few times already. I have never questioned the accuracy, others have. I've said all I have to say on the subject for the time being. Any other discussion at this point is going to lead to back and forth nastiness it appears. No you haven't. Post the peer review papers in this thread. I would love to see those papers. Ive never found them. the 20cm error margin was released with the revised data two days ago. the same place the volume and thickness data come from. Of course you have nothing to say, your lying about the countless peer review papers. The new data is revised and is way different from the first map. It looks like, you guessed it piomas thickness. Now that cryosat validates piomas no one is talking about it. Except your trying to hide the data or something. 7 months of thickness data doesnt lie Link to comment Share on other sites More sharing options...
LithiaWx Posted April 26, 2012 Share Posted April 26, 2012 No you haven't. Post the peer review papers in this thread. I would love to see those papers. Ive never found them. the 20cm error margin was released with the revised data two days ago. the same place the volume and thickness data come from. Of course you have nothing to say, your lying about the countless peer review papers. The new data is revised and is way different from the first map. It looks like, you guessed it piomas thickness. Now that cryosat validates piomas no one is talking about it. Except your trying to hide the data or something. 7 months of thickness data doesnt lie Countless papers http://scholar.googl...ved=0CBgQgQMwAA From fall of 2011 http://adsabs.harvar...AGUFM.C53F..01W The 20cm number has been known for a lot longer than two days. Abstract Following the launch of CryoSat-2 in April 2010, we have examined the performance of the CryoSat-2 SAR Interferometer over the continental ice sheets of Antarctica and Greenland, the Artic Ocean, and, for the purposes of calibration, over the oceans. Our aim has been to provide confirmation of the engineering performance of the radar interferometer, and to provide an initial geophysical validation of the resulting elevation measurements. We have confirmed the engineering performance at system level of the interferometer through performing a sequence of satellite rolls over the oceans, which provide a surface of known behavior and surface gradient. The activity has identified some errors in the SARIN L1b data products presently issued by ESA. Once corrected, the ocean calibration has demonstrated that the interferometer measures across-track surface slopes with a precision of 25 micro-radians and an accuracy of 10 micro-radians, which may be compared with a pre-launch estimation of 100 micro-radians; in short, the engineering performance greatly its the specification. The elevation measurement over the ice sheets combines the interferometer measurement of across track slope with the range measurement deduced from the SAR echoes. We have examined the performance of the range estimation, and determined the range precision to be 19 cm RMS at 20 Hz. We have examined the retrieval of the phase information over the ice sheets, and found the phase estimates to be robust and little affected by the uncertain ice sheet topography. Based on the calibration of the interferometer, the contribution of the across track slope error is, at 0.4 mm, negligible. While the quantity of data available to us that contains the corrections identified by the interferometer is limited, we have been able to confirm the range precision values from a limited cross-over analysis. Over marine sea ice, we have verified the discrimination of sea ice and ocean lead returns using contemporaneous SAR imagery from ENVISAT. Using one month's of data, we have determined an initial dynamic topography that agrees with a high resolution region ocean model to 4 cm. We have estimated the precision of individual (20 Hz) measurements to be 2 cm. We have combined estimated the Arctic ice thickness for January and February 2011, and made a preliminary comparison with contemporaneous in-situ and air-borne estimates of thickness which agree to 20 cm. In summary, with the corrected data products, we are able to confirm that the system performance of CryoSat-2 will meet or exceed its specification over the continental and marine ice sheets. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted April 26, 2012 Share Posted April 26, 2012 Countless papers http://scholar.googl...ved=0CBgQgQMwAA From fall of 2011 http://adsabs.harvar...AGUFM.C53F..01W The 20cm number has been known for a lot longer than two days. The first link had one paper on the first 5 pages mentioning cryosat data in real time. That was the paper in which you posted the abstract. Unfortunitely they do not specify the context. I have no doubt cryosat can deliver. but sonewhere along the line they trashed the Jan-Feb prelim map for the ones just released. There is a huge difference between them. It is clear why they were silent for so long. They let that prelim map out and quickly realized somewhere they bleeped the bed. however when you look at them. The patterns the same. So they used the same data but must have calibrated the scale wrong or something. my entire issue isn't that cryosat isn't that accurate. Its the physical impossibitie the first graph had these new ones seem more legit. Link to comment Share on other sites More sharing options...
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