WHAT'S NEW?

DATEISSUES
12/6/2007

Unrealistic Values in Fram Strait

It was recently brought to our attention by Christophe Herbaut and Marie-Noelle Houssais that Fram Strait has some strange salinity values in PHC 3.0. Most notable are unusually high salinity values in January spreading across Fram Strait at about 800m, and anomalously low salinity values in the November field around 1200m.

The source of this problem is the WOA '98 fields which predominate in Fram Strait in PHC 3.0. Another issue introduced by the WOA '98 fields in Fram Strait occurs around latitude 75.5 as isolated anomalies at depth in all temperature fields. These isolated anomalies look like there was a single profile taken within the East Greenland Current and another within the Norwegian Atlantic Current. The WOA OI routine then creates isolated coastal anomalies, which would appear as boundary currents if there were more data within each of these currents. To make these currents more realistic would require obtaining more data and re-doing the OI in this region, a task we leave for the future!

The latest version of WOA (2005) represents Fram Strait a little more realistically than WOA '98. While the isolated temperature anomalies remain, they are not as severe, and the salinity issues in the monthly fields go away entirely.

PHC is therefore being updated to incorporate WOA '05, and should be available early in 2008. The problems in Bering Strait (posted 8/7/2006) will also be addressed in the new PHC 4.0 release.


click for more details
8/7/2006

Bad values discovered in Bering Strait

Some questionable values have been discovered in PHC 3.0 in Bering Strait, shown as blue dots on the plot to the right. The unrealistic data occur in the winter seasonal PHC 3.0 fields, and therefore in the monthly fields during Dec-May as well. The anomalies are higher than expected values in both salinity and temperature at depth. For more details about this problem, click on the plot.

This problem was brought to our attention by Dr. Marie-Noelle Houssais, for which we are very thankful.

Locations of problem data in PHC 3.0

click for more details
5/30/06

PHC 3.0 is available in ODV format

Great thanks to Reiner Schlitzer for providing the following for PHC users!

The "Polar science center Hydrographic Climatology" (PHC3.0) of Steele, Morley, and Ermold (2005) is now available for download at

http://odv.awi-bremerhaven.de/data/ocean/phc-30.html

There are four collections containing the annual, summer, winter and monthly PHC data, respectively. The data are in ODV collection format and ready to be used by Ocean Data View.

Best regards,

R. Schlitzer
3/3/05

PHC HAS BEEN UPDATED!


PHC 2.1 has been upgraded to PHC 3.0. This upgrade corrects the BUG identified on 2/4/2004, and also another a density instability problem that was brought to our attention by Jinlun Zhang of the Polar Science Center in Seattle, Washington. More details about these issues with PHC 2.1, and how we fixed them in PHC 3.0, can be found by clicking on the PHC 3.0 link on the Technical Details page of this report.
2/4/04
**BUG ALERT**
It was brought to our attention by Ralf Doscher, of the Swedish Meteorological and Hydrological Institute (SMHI), that there is a slight anomaly in our temperature fields around latitude 83N. This feature, illustrated at right, exists in both the summer and winter fields, and most of the monthly fields, and is on the order .1 degrees C. A corrected version of PHC will be available within the next few months.
PHC 2.1 Summer Temperature
3/1/04The poisson solver program provided on the data page (fill_land.f) was modified to be a bit more user friendly toward PHC 2.1 data. Additional comments within the program were also provided to help the user know what lines to modify depending on the data being analyzed.
5/29/03The site was rearranged in a couple of ways:

  1. The PHC 2.1 Overview was modified to be more brief. Much of the original contents were moved to a newly created link on the contents page: About the Upgrade from PHC 2.0.
  2. The graphics from the "Graphical Analysis" section of the PHC 2.1 detailed report were moved:

    PHC 2.1 vs PHC 2.0 Comparison Plots are now in the "About the Upgrade to PHC 2.0" section.
    PHC 2.1 Profiles are in the Season Fields/Sample Graphics link on the contents page: Season Fields/Sample Graphics
5/21/03The PHC 2.1 Detailed Report was posted in its entirety.
12/23/02Most of this web site was posted, except for the "PHC 2.1 Detailed Report".













Return to Table of Contents