! $Id: ice_calendar.F90 1200 2017-04-18 21:08:54Z tcraig $ !======================================================================= ! Calendar routines for managing time ! ! authors: Elizabeth C. Hunke, LANL ! Tony Craig, NCAR ! Craig MacLachlan, UK Met Office ! ! 2006 ECH: Removed 'w' option for history; added 'h' and histfreq_n. ! Converted to free form source (F90). ! 2010 CM : Fixed support for Gregorian calendar: subroutines ! sec2time, time2sec and set_calendar added. module ice_calendar use ice_kinds_mod use ice_constants, only: c0, c1, c100, c30, c360, c365, c3600, & c4, c400, secday use ice_domain_size, only: max_nstrm use ice_exit, only: abort_ice implicit none private save public :: init_calendar, calendar, time2sec, sec2time integer (kind=int_kind), public :: & days_per_year , & ! number of days in one year daymo(12) , & ! number of days in each month daycal(13) ! day number at end of month ! 360-day year data integer (kind=int_kind) :: & daymo360(12) , & ! number of days in each month daycal360(13) ! day number at end of month data daymo360 / 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30/ data daycal360/ 0,30, 60, 90,120,150,180,210,240,270,300,330,360/ ! 365-day year data integer (kind=int_kind) :: & daymo365(12) , & ! number of days in each month daycal365(13) ! day number at end of month data daymo365 / 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31/ data daycal365/ 0,31, 59, 90,120,151,181,212,243,273,304,334,365/ ! 366-day year data (leap year) integer (kind=int_kind) :: & daymo366(12) , & ! number of days in each month daycal366(13) ! day number at end of month data daymo366 / 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31/ data daycal366/ 0,31, 60, 91,121,152,182,213,244,274,305,335,366/ real (kind=dbl_kind), parameter :: & days_per_4c = 146097.0_dbl_kind, & days_per_c = 36524.0_dbl_kind, & days_per_4y = 1461.0_dbl_kind, & days_per_y = 365.0_dbl_kind integer (kind=int_kind), public :: & istep , & ! local step counter for time loop istep0 , & ! counter, number of steps taken in previous run istep1 , & ! counter, number of steps at current timestep mday , & ! day of the month hour , & ! hour of the year month , & ! month number, 1 to 12 monthp , & ! last month year_init, & ! initial year nyr , & ! year number idate , & ! date (yyyymmdd) idate0 , & ! initial date (yyyymmdd) sec , & ! elapsed seconds into date npt , & ! total number of time steps (dt) ndtd , & ! number of dynamics subcycles: dt_dyn=dt/ndtd stop_now , & ! if 1, end program execution write_restart, & ! if 1, write restart now diagfreq , & ! diagnostic output frequency (10 = once per 10 dt) dumpfreq_n , & ! restart output frequency (10 = once per 10 d,m,y) nstreams , & ! number of history output streams histfreq_n(max_nstrm) ! history output frequency real (kind=dbl_kind), public :: & dt , & ! thermodynamics timestep (s) dt_dyn , & ! dynamics/transport/ridging timestep (s) time , & ! total elapsed time (s) time_forc , & ! time of last forcing update (s) yday , & ! day of the year tday , & ! absolute day number dayyr , & ! number of days per year nextsw_cday , & ! julian day of next shortwave calculation basis_seconds ! Seconds since calendar zero logical (kind=log_kind), public :: & new_year , & ! new year = .true. new_month , & ! new month = .true. new_day , & ! new day = .true. new_hour , & ! new hour = .true. use_leap_years , & ! use leap year functionality if true write_ic , & ! write initial condition now dump_last , & ! write restart file on last time step force_restart_now, & ! force a restart now write_history(max_nstrm) ! write history now character (len=1), public :: & histfreq(max_nstrm), & ! history output frequency, 'y','m','d','h','1' dumpfreq ! restart frequency, 'y','m','d' character (len=char_len), public :: & calendar_type ! differentiates Gregorian from other calendars ! default = ' ' !======================================================================= contains !======================================================================= ! Initialize calendar variables ! ! authors: Elizabeth C. Hunke, LANL ! Tony Craig, NCAR ! Craig MacLachlan, UK Met Office subroutine init_calendar use ice_fileunits, only: nu_diag istep = 0 ! local timestep number time=istep0*dt ! s yday=c0 ! absolute day number mday=0 ! day of the month month=0 ! month nyr=0 ! year idate=00000101 ! date sec=0 ! seconds into date istep1 = istep0 ! number of steps at current timestep ! real (dumped) or imagined (use to set calendar) stop_now = 0 ! end program execution if stop_now=1 dt_dyn = dt/real(ndtd,kind=dbl_kind) ! dynamics et al timestep force_restart_now = .false. ! Check that the number of days per year is set correctly when using ! leap years. If not, set days_per_year correctly and warn the user. if (use_leap_years .and. days_per_year /= 365) then days_per_year = 365 write(nu_diag,*) 'Warning: days_per_year has been set to 365', & ' because use_leap_years = .true.' end if #ifdef CCSMCOUPLED ! calendar_type set by coupling #else calendar_type = ' ' if (use_leap_years .and. days_per_year == 365) calendar_type = 'Gregorian' #endif dayyr = real(days_per_year, kind=dbl_kind) if (days_per_year == 360) then daymo = daymo360 daycal = daycal360 elseif (days_per_year == 365) then daymo = daymo365 daycal = daycal365 else call abort_ice('ice: days_per_year must be 360 or 365') endif ! Get the time in seconds from calendar zero to start of initial year call time2sec(year_init,1,1,basis_seconds) ! determine initial date (assumes namelist year_init, istep0 unchanged) sec = mod(time,secday) ! elapsed seconds into date at ! end of dt tday = (time-sec)/secday + c1 ! absolute day number ! Convert the current timestep into a calendar date call sec2time(nyr,month,mday,basis_seconds+sec) yday = mday + daycal(month) ! day of the year nyr = nyr - year_init + 1 ! year number idate0 = (nyr+year_init-1)*10000 + month*100 + mday ! date (yyyymmdd) end subroutine init_calendar !======================================================================= ! Determine the date at the end of the time step ! ! authors: Elizabeth C. Hunke, LANL ! Tony Craig, NCAR ! Craig MacLachlan, UK Met Office subroutine calendar(ttime) use ice_fileunits, only: nu_diag use ice_communicate, only: my_task, master_task real (kind=dbl_kind), intent(in) :: & ttime ! time variable ! local variables integer (kind=int_kind) :: & ns , & ! loop index nyrp,mdayp,hourp , & ! previous year, day, hour elapsed_days , & ! since beginning this run elapsed_months , & ! since beginning this run elapsed_hours , & ! since beginning this run month0 nyrp=nyr monthp=month mdayp=mday hourp=hour new_year=.false. new_month=.false. new_day=.false. new_hour=.false. write_history(:)=.false. write_restart=0 sec = mod(ttime,secday) ! elapsed seconds into date at ! end of dt tday = (ttime-sec)/secday + c1 ! absolute day number ! Deterime the current date from the timestep call sec2time(nyr,month,mday,basis_seconds+ttime) yday = mday + daycal(month) ! day of the year nyr = nyr - year_init + 1 ! year number hour = int((ttime)/c3600) + c1 ! hour month0 = int((idate0 - int(idate0 / 10000) * 10000) / 100) elapsed_months = (nyr - 1)*12 + (month - month0) elapsed_days = int((istep * dt) / secday) elapsed_hours = int(ttime/3600) idate = (nyr+year_init-1)*10000 + month*100 + mday ! date (yyyymmdd) #ifndef CCSMCOUPLED if (istep >= npt+1) stop_now = 1 if (istep == npt .and. dump_last) write_restart = 1 ! last timestep #endif if (nyr /= nyrp) new_year = .true. if (month /= monthp) new_month = .true. if (mday /= mdayp) new_day = .true. if (hour /= hourp) new_hour = .true. do ns = 1, nstreams if (histfreq(ns)=='1' .and. histfreq_n(ns)/=0) then if (mod(istep1, histfreq_n(ns))==0) & write_history(ns)=.true. endif enddo if (istep > 1) then do ns = 1, nstreams select case (histfreq(ns)) case ("y", "Y") if (new_year .and. histfreq_n(ns)/=0) then if (mod(nyr, histfreq_n(ns))==0) & write_history(ns) = .true. endif case ("m", "M") if (new_month .and. histfreq_n(ns)/=0) then if (mod(elapsed_months,histfreq_n(ns))==0) & write_history(ns) = .true. endif case ("d", "D") if (new_day .and. histfreq_n(ns)/=0) then if (mod(elapsed_days,histfreq_n(ns))==0) & write_history(ns) = .true. endif case ("h", "H") if (new_hour .and. histfreq_n(ns)/=0) then if (mod(elapsed_hours,histfreq_n(ns))==0) & write_history(ns) = .true. endif end select enddo ! nstreams select case (dumpfreq) case ("y", "Y") if (new_year .and. mod(nyr, dumpfreq_n)==0) & write_restart = 1 case ("m", "M") if (new_month .and. mod(elapsed_months,dumpfreq_n)==0) & write_restart = 1 case ("d", "D") if (new_day .and. mod(elapsed_days, dumpfreq_n)==0) & write_restart = 1 end select if (force_restart_now) write_restart = 1 endif ! istep > 1 if (my_task == master_task .and. mod(istep,diagfreq) == 0 & .and. stop_now /= 1) then write(nu_diag,*) ' ' write(nu_diag,'(a7,i10,4x,a6,i10,4x,a4,i10)') & 'istep1:', istep1, 'idate:', idate, 'sec:', sec endif end subroutine calendar !======================================================================= ! Convert the date to seconds since calendar zero. ! ** This is based on the UM routine TIME2SEC ** ! ! authors: Craig MacLachlan, UK Met Office subroutine time2sec(year,month,day,tsec) integer (kind=int_kind), intent(in) :: year ! year integer (kind=int_kind), intent(in) :: month ! month integer (kind=int_kind), intent(in) :: day ! year real (kind=dbl_kind), intent(out) :: tsec ! seconds since calendar zero ! local variables real (kind=dbl_kind) :: days_since_calz ! days since calendar zero integer (kind=int_kind) :: years_since_calz ! days since calendar zero if (dayyr == 360) then days_since_calz = c360*year + c30*(month-1) + day - c1 tsec = secday * days_since_calz else if (use_leap_years) then call set_calendar(year) ! Add on the days from this year days_since_calz = day + daycal(month) - c1 ! Subtract a year because we only want to count whole years years_since_calz = year - 1 ! Add days from preceeding years days_since_calz = days_since_calz & + int(years_since_calz/c400)*days_per_4c years_since_calz = years_since_calz & - int(years_since_calz/c400)*400 days_since_calz = days_since_calz & + int(years_since_calz/c100)*days_per_c years_since_calz = years_since_calz & - int(years_since_calz/c100)*100 days_since_calz = days_since_calz & + int(years_since_calz/c4)*days_per_4y years_since_calz = years_since_calz & - int(years_since_calz/c4)*4 days_since_calz = days_since_calz & + years_since_calz*days_per_y tsec = secday * days_since_calz else ! Using fixed 365-day calendar days_since_calz = c365*year + daycal365(month) + day - c1 tsec = secday * days_since_calz end if end if end subroutine time2sec !======================================================================= ! Convert the time in seconds since calendar zero to a date. ! ! authors: Craig MacLachlan, UK Met Office subroutine sec2time(year,month,day,tsec) integer (kind=int_kind), intent(out) :: year ! year integer (kind=int_kind), intent(out) :: month ! month integer (kind=int_kind), intent(out) :: day ! year real (kind=dbl_kind), intent(in) :: tsec ! seconds since calendar zero ! local variables real (kind=dbl_kind) :: days_since_calz ! days since calendar zero integer (kind=int_kind) :: k ! counter days_since_calz = int(tsec/secday) if (dayyr == 360) then year = int(days_since_calz/c360) month = mod(int(days_since_calz/c30),12) + 1 day = mod(int(days_since_calz),30) + 1 else if (use_leap_years) then year = int(days_since_calz/days_per_4c)*400 days_since_calz = days_since_calz & - int(days_since_calz/days_per_4c)*days_per_4c if (days_since_calz == 4*days_per_c) then year = year + 400 days_since_calz = days_per_y + 1 else year = year + int(days_since_calz/days_per_c)*100 days_since_calz = days_since_calz & - int(days_since_calz/days_per_c)*days_per_c year = year + int(days_since_calz/days_per_4y)*4 days_since_calz = days_since_calz & - int(days_since_calz/days_per_4y)*days_per_4y if (days_since_calz == 4*days_per_y) then year = year + 4 days_since_calz = days_per_y + 1 else year = year + int(days_since_calz/days_per_y) + 1 days_since_calz = days_since_calz & - int(days_since_calz/days_per_y)*days_per_y + c1 endif endif ! Ensure the calendar variables are correct for this year. call set_calendar(year) ! Calculate the month month = 1 do k = 1, 12 if (days_since_calz > daycal(k)) month = k enddo ! Calculate the day of the month day = days_since_calz - daycal(month) else ! Using fixed 365-day calendar year = int(days_since_calz/c365) days_since_calz = days_since_calz - year*365 + 1 ! Calculate the month month = 1 do k = 1, 12 if (days_since_calz > daycal365(k)) month = k enddo ! Calculate the day of the month day = days_since_calz - daycal365(month) end if end if end subroutine sec2time !======================================================================= ! Set the "days per month", "days per year", etc variables for the ! current year. ! ! authors: Craig MacLachlan, UK Met Office subroutine set_calendar(year) integer (kind=int_kind), intent(in) :: year ! current year ! Internal variable logical (kind=log_kind) :: isleap ! Leap year logical isleap = .false. ! not a leap year if (mod(year, 4) == 0) isleap = .true. if (mod(year,100) == 0) isleap = .false. if (mod(year,400) == 0) isleap = .true. ! Ensure the calendar is set correctly if (isleap) then daycal = daycal366 daymo = daymo366 dayyr=real(daycal(13), kind=dbl_kind) days_per_year=int(dayyr) else daycal = daycal365 daymo = daymo365 dayyr=real(daycal(13), kind=dbl_kind) days_per_year=int(dayyr) endif end subroutine set_calendar !======================================================================= end module ice_calendar !=======================================================================