Minimum Insolation Over A Consecutive pday Period
Minimum Insolation Over A Consecutive pday Period
This parameter used to be given as a percentage and is defined as such:
Climatology: The minimum available insolation over a consecutive pday period (p=1, 3, 7, 14, or 21 days) in a particular month is given as the % difference between the minimum monthly average value over the pday period and the monthly average value for the pday period. The pday average is computed as a running average within each month. The monthly average for the pday period is calculated as a multiyear average over the climatological period given in the header section of the data file.
Now the Unit is kWhr/m^2/day.
How should we interpret this new unit? Is it the minimum cumulative amount of insolation expected over pdays? Is it the difference of cumulative insolation between minimum and average values over pdays? Or should we interpret this information differently.
Thank you,
Jeff
Climatology: The minimum available insolation over a consecutive pday period (p=1, 3, 7, 14, or 21 days) in a particular month is given as the % difference between the minimum monthly average value over the pday period and the monthly average value for the pday period. The pday average is computed as a running average within each month. The monthly average for the pday period is calculated as a multiyear average over the climatological period given in the header section of the data file.
Now the Unit is kWhr/m^2/day.
How should we interpret this new unit? Is it the minimum cumulative amount of insolation expected over pdays? Is it the difference of cumulative insolation between minimum and average values over pdays? Or should we interpret this information differently.
Thank you,
Jeff
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Re: Minimum Insolation Over A Consecutive pday Period
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Re: Minimum Insolation Over A Consecutive pday Period
Jeff,
Yes, there was a change in the consecutive pday period parameters; we now provide the insolation value not a percentage. We have updated the parameter definitions to reflect this change.
The value is the cumulative minimum amount of insolation over the pdays period.
Since we now provide the insolation value, the percentage can be calculated following the example below:
INSOL_CONSEC_07_MIN / INSOL_CONSEC_07 = %
Thank you,
The NASA POWER Team
Prediction Of Worldwide Energy Resources (POWER)
NASA Earth Science/Applied Science Program
NASA Langley Research Center (LaRC)
POWER Documentation & FAQs
Yes, there was a change in the consecutive pday period parameters; we now provide the insolation value not a percentage. We have updated the parameter definitions to reflect this change.
The value is the cumulative minimum amount of insolation over the pdays period.
Since we now provide the insolation value, the percentage can be calculated following the example below:
INSOL_CONSEC_07_MIN / INSOL_CONSEC_07 = %
Thank you,
The NASA POWER Team
Prediction Of Worldwide Energy Resources (POWER)
NASA Earth Science/Applied Science Program
NASA Langley Research Center (LaRC)
POWER Documentation & FAQs
Re: Minimum Insolation Over A Consecutive pday Period
In the Power Access application, if I wish to get the INSOL_CONSEC_07, which option should I select from the list?
When I select "Insolation Over A Consecutive pday Period" I get INSOL_CONSEC_07 but it is described as "Surplus Insolation Over a Consecutive pday Period" which is defined as:
"Available Surplus Insolation Over A Consecutive pday period in a particular month is given as the irradiance value between the maximum monthly average value over the pday period and the monthly average value for the pday period. The pday average is computed as a running average within each month. The monthly average for the pday period is calculated as a multiyear average over the climatological period given in the header section of the data file."
Is this definition correct? Why would I divide by the surplus insolation between average a max when I am looking for the percentage difference between MIN and Average insolation over pdays?
When I select "Insolation Over A Consecutive pday Period" I get INSOL_CONSEC_07 but it is described as "Surplus Insolation Over a Consecutive pday Period" which is defined as:
"Available Surplus Insolation Over A Consecutive pday period in a particular month is given as the irradiance value between the maximum monthly average value over the pday period and the monthly average value for the pday period. The pday average is computed as a running average within each month. The monthly average for the pday period is calculated as a multiyear average over the climatological period given in the header section of the data file."
Is this definition correct? Why would I divide by the surplus insolation between average a max when I am looking for the percentage difference between MIN and Average insolation over pdays?

 User Services
 Posts: 14
 Joined: Mon Nov 23, 2020 3:57 pm America/New_York
Re: Minimum Insolation Over A Consecutive pday Period
Hi Jeff,
The POWER team has advised that they are still evaluating your additional questions and will provide a response soon.
Thanks,
ASDC User Services
The POWER team has advised that they are still evaluating your additional questions and will provide a response soon.
Thanks,
ASDC User Services