AGCD: conversions required to comply with ALMA/CF

[aukkola]

We recommend not using AGCD at this point as radiation is not publicly available. ANUCLIMATE provides an open source, published alternative.

But here are a list of issues that would need to be considered:

• Data is daily, will need to use a weather generator to go sub-daily (can use equations in BIOS that are provided in CABLE Fortran code. These are very basic but will do for now)
• Unit conversions needed (rainfall, temperature)
• Need to calculate specific humidity from 9am/3pm vapour pressure (BIOS has equations to do this)
• No radiation or wind speed data available. Need to use another data source
• Longwave radiation not available but can be synthesised from Swinbank equation used in CABLE (available in cable_input.F90): met%fld(:) = 0.0000094*0.0000000567*(met%tk(:)**6.0)
• Precip should be taken from AGCD v2, other variables are only available in v1