From 1cddc8474d3f3621d49a1b8c45b4c3919eba8728 Mon Sep 17 00:00:00 2001
From: Mads Hvid Ribergaard <38077893+mhrib@users.noreply.github.com>
Date: Tue, 20 Apr 2021 17:54:07 +0200
Subject: [PATCH] Remove hc_jday and replace with "compute_days_between" for
 HYCOM forcing (#597)

* Remove hc_jday. Not used anymore after introducing of new ice_calendar

* Calculate "hc_jday" inline using compute_days_between and _init fields from ice_calendar

* Correct hcdate using "compute_days_between"

* Remove unused variables from ice_calendar
---
 cicecore/cicedynB/general/ice_forcing.F90 |  6 +--
 cicecore/shared/ice_calendar.F90          | 48 -----------------------
 2 files changed, 3 insertions(+), 51 deletions(-)
 mode change 100644 => 100755 cicecore/cicedynB/general/ice_forcing.F90

diff --git a/cicecore/cicedynB/general/ice_forcing.F90 b/cicecore/cicedynB/general/ice_forcing.F90
old mode 100644
new mode 100755
index d18b1ccd7..186e50f6c
--- a/cicecore/cicedynB/general/ice_forcing.F90
+++ b/cicecore/cicedynB/general/ice_forcing.F90
@@ -24,7 +24,7 @@ module ice_forcing
       use ice_communicate, only: my_task, master_task
       use ice_calendar, only: istep, istep1, &
                               msec, mday, mmonth, myear, yday, daycal, &
-                              daymo, days_per_year, hc_jday
+                              daymo, days_per_year, compute_days_between
       use ice_fileunits, only: nu_diag, nu_forcing
       use ice_exit, only: abort_ice
       use ice_read_write, only: ice_open, ice_read, &
@@ -4607,8 +4607,8 @@ subroutine hycom_atm_data
       call icepack_query_parameters(Tffresh_out=Tffresh)
       call icepack_query_parameters(secday_out=secday)
 
-      ! current time in HYCOM jday units
-      hcdate = hc_jday(myear,0,0)+ yday+msec/secday
+      ! current time in HYCOM jday units (HYCOM ref year: 1900,12,31,000000) 
+      hcdate = real(compute_days_between(1900,12,31,myear,mmonth,mday)) + msec/secday
 
       ! Init recnum try
       recnum=min(max(oldrecnum,1),Njday_atm-1)
diff --git a/cicecore/shared/ice_calendar.F90 b/cicecore/shared/ice_calendar.F90
index 8158313d9..4d7ae378f 100644
--- a/cicecore/shared/ice_calendar.F90
+++ b/cicecore/shared/ice_calendar.F90
@@ -36,7 +36,6 @@ module ice_calendar
       public :: set_date_from_timesecs ! set model date from time in seconds
                                        ! (relative to init date)
                                        ! needed for binary restarts
-      public :: hc_jday  ! converts "calendar" date to HYCOM julian day
 
       ! semi-private, only used directly by unit tester
       public :: compute_elapsed_days ! compute elapsed days since 0000-01-01
@@ -916,53 +915,6 @@ subroutine calendar_time2date(atimesecs,ayear,amon,aday,asec,year_ref,mon_ref,da
 
       end subroutine calendar_time2date
 
-!=======================================================================
-
-      real(kind=dbl_kind) function hc_jday(iyear,imm,idd,ihour)
-!--------------------------------------------------------------------
-! converts "calendar" date to HYCOM julian day:
-!   1) year,month,day,hour  (4 arguments)
-!   2) year,doy,hour        (3 arguments)
-!
-! HYCOM model day is calendar days since 31/12/1900
-!--------------------------------------------------------------------
-        real(kind=dbl_kind)     :: dtime
-        integer(kind=int_kind)  :: iyear,iyr,imm,idd,idoy,ihr
-        integer(kind=int_kind), optional :: ihour
-        integer (kind=int_kind) :: n
-
-        if (present(ihour)) then
-          !-----------------
-          ! yyyy mm dd HH
-          !-----------------
-          iyr=iyear-1901
-          dtime = floor(365.25_dbl_kind*iyr)*c1 + idd*c1 + ihour/24._dbl_kind
-          if (mod(iyr,4)==3) then
-            do n = 1,imm-1
-               dtime = dtime + daymo366(n)
-            enddo
-          else
-            do n = 1,imm-1
-               dtime = dtime + daymo365(n)
-            enddo
-          endif
-
-        else
-          !-----------------
-          ! yyyy DOY HH
-          !-----------------
-          ihr   = idd   ! redefine input
-          idoy  = imm   ! redefine input
-          iyr   = iyear - 1901
-          dtime = floor(365.25_dbl_kind*iyr)*c1 + idoy*c1 + ihr/24._dbl_kind
-
-        endif
-
-        hc_jday=dtime
-
-        return
-      end function hc_jday
-
 !=======================================================================
 
       end module ice_calendar