Author: Gérard Petit (IERS Conventions Center)

Information on the updates to the IERS Conventions (2010)

The IERS Conventions Center informs of the following updates:

10 August 2012

* Chapter 5 "Transformation between the ITRS and GCRS" has been updated, see http://tai.bipm.org/iers/convupdt/convupdt_c5.html .

          o Report the yearly update fcnnut120701 to the Free Core Nutation model and correct a typo in the value of the FCN period.

* Chapter 6 "Geopotential" has been updated, see http://tai.bipm.org/iers/convupdt/convupdt_c6.html .

          o In the section 6.3.2 "Ocean tide models", part "FES2004", it is specified how to treat the zonal terms in order to get consistent values for the Stokes coefficients.

* Chapter 9 "Models for atmospheric propagation delays" has been updated, see http://tai.bipm.org/iers/convupdt/convupdt_c9.html .

          o In the section 9.2 "Tropospheric model for radio techniques", correct a typo in the Cheng and Herring gradient mapping function.

          o In the section 9.4.1 "Ionospheric delay dependence on radio signals including higher order terms", the part "Ray bending effects on geometric path excess and ionospheric delay" has been updated (from E. Petrie and M. Hernandez Pajares).

Announcement for the following past updates were not circulated in due time:

21 December 2011

* Chapter 8 "Tidal variations in the Earth´s rotation" has been updated, see http://tai.bipm.org/iers/convupdt/convupdt_c8.html .

The subroutine RG_ZONT2 has been corrected for a typo in the sine coefficient of the 365.26 period for delta LOD (Noted by J. Lundberg). The effect is of order a ns in the length of day.

* The Glossary has been updated, see http://tai.bipm.org/iers/convupdt/convupdt_gl.html .

In the term "celestial pole offsets", "IAU 2000A" should be replaced by "IAU 2006/2000".

26 March 2012

* Chapter7 " Displacements of reference points " has been updated, see http://tai.bipm.org/iers/convupdt/convupdt_c7.html .

Have been modified to account for the next leap second to occur June 30, 2012:

          o The subroutine HARDISP.F and its subroutine ETUTC.F

          o The subroutine DEHANTTIDEINEL.F and its subroutines from the SOFA package DAT.F and CAL2JD.F.

Note that the previous version of DEHANTTIDEINEL.F, which is the one available on the Conventions 2010 web page, erroneously did not include an update dated April 10, 2009. The new version reinstalls this update (a 0.05 mm effect).

* Chapter 9 "Models for atmospheric propagation delays" has been updated, see http://tai.bipm.org/iers/convupdt/convupdt_c9.html .

The test case provided for the subroutine VMF1.F has been corrected.

The subroutine VMF1_HT.F has been corrected for an error in the computation of the quantity VMF1H (noted by J. McCarthy) and for the test case.

The USNO web site http://maia.usno.navy.mil/conv2010/convupdt.html will be updated shortly.

Gérard Petit and Brian Luzum

IERS Conventions Center