DQR ID | Subject | Data Streams Affected |
---|
D090831.1 | GRW/SKYRAD/M1 - Daily brief instrument shading | grwskyrad20sM1.a0, grwskyrad60sM1.b1 |
D091228.1 | GRW/SKYRAD/M1 - AOS tower Obstruction | grwskyrad20sM1.a0, grwskyrad60sM1.b1 |
D100209.3 | GRW/TSI/M1 - Shadowband Misalignment | grwtsiskycoverM1.b1, grwtsiskyimageM1.a1, grwtsicldmaskM1.a1 |
D100511.1 | GRW/TSI/M1 - Contamination of mirror | grwtsicldmaskM1.a1, grwtsimovieM1.a1, grwtsiskycoverM1.b1, grwtsiskyimageM1.a1 |
D100606.1 | GRW/SKYRAD/M1 - Short direct normal questionable | grwskyrad20sM1.a0, grwskyrad60sM1.b1 |
D110505.1 | GRW/TSI/M1 - Shadowband Misalignment | grwtsiskycoverM1.b1 |
D110513.8 | GRW/NFOV/M1 - Data over-ranging | grwnfov2chM1.b1 |
D110610.1 | GRW/NFOV/M1 - Missing data | grwnfov2chM1.b1 |
D120816.1 | GRW/IRT/M1 - Serial communication problem | grwirt200msM1.a1, grwirtM1.b1 |
D130718.8 | GRW/TSI/M1 - Data processing problem | grwtsiskycoverM1.b1 |
D130807.5 | GRW/TSI/M1 - Incorrect units | grwtsiskycoverM1.b1 |
Subject: | GRW/SKYRAD/M1 - Daily brief instrument shading |
DataStreams: | grwskyrad20sM1.a0, grwskyrad60sM1.b1
|
Description: | Due to the persistent cloudy conditions at this site this shading of the NIP and PSP is
rarely evident in the data. But from approximately 1745 to 1810 GMT from 8/26 to 10/23 and
from 3/01 to 4/18 during the AMF deployment years 2009 and 2010, the NIP and PSP are
shaded by the 10m met tower to the SE of the Skystand.
Data review indicates that the NIP (short_direct_normal) and PSP (down_short_hemisp) are
shaded by a single tower pole and possibly other tower mounted objects. The data are not
correctable but the azimuth and zenith windows to avoid are:
short_direct_normal (NIP instrument)
Zenith angle > 62 deg
254 deg < Azimuth angle < 262 deg
primary obstruction at 255 deg Az
down_short_diffuse(PSP instrument)
Zenith angle > 59 deg
246 deg < Azimuth angle < 257 deg
primary obstruction at 251.5 deg Az
Date ranges this problem will exist for are:
20090301-20090418 (pre-official deployment, data exist)
20090826-20091023
20100301-20100418
20100826-20101023
The QCrad VAP should flag bad data points via its QC logic. Users should either exclude
the data within the windows above or review data for outliers in these zenith, azimuth
angles. |
Measurements: | grwskyrad20sM1.a0: - inst_direct_normal
- inst_global
grwskyrad60sM1.b1: - Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Minima(down_short_hemisp_min)
- Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Maxima(down_short_hemisp_max)
- Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)
- Shortwave Direct Normal Irradiance, Pyrheliometer, Minima(short_direct_normal_min)
- Shortwave Direct Normal Irradiance, Pyrheliometer, Maxima(short_direct_normal_max)
- down_short_hemisp_std
- short_direct_normal_std
- Radiation, shortwave, downwelling total hemispheric irradiance, 1-min avg(down_short_hemisp)
|
Subject: | GRW/SKYRAD/M1 - AOS tower Obstruction |
DataStreams: | grwskyrad20sM1.a0, grwskyrad60sM1.b1
|
Description: | Due to the persistent cloudy conditions at this site the shading is rarely evident in the
data. But at approximately 1010GMT everyday during from approximately 12/2/2009 to
1/11/2010 the NIP is shaded by the AOS tower. Data review indicates that only the NIP
(short_direct_normal) is obstructed when the sun is at 130 to 132 deg azimuth during the time
period specified.
NIP data are not recoverable. However, short_direct_normal can be reconstructed by
applying the following formula:
Short_direct_normal = (down_short_hemisp-down_short_diffuse_hemisp)/cos(Zenith angle) |
Measurements: | grwskyrad20sM1.a0:
grwskyrad60sM1.b1: - Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)
- Shortwave Direct Normal Irradiance, Pyrheliometer, Minima(short_direct_normal_min)
- Shortwave Direct Normal Irradiance, Pyrheliometer, Maxima(short_direct_normal_max)
- short_direct_normal_std
|
Subject: | GRW/TSI/M1 - Shadowband Misalignment |
DataStreams: | grwtsiskycoverM1.b1, grwtsiskyimageM1.a1, grwtsicldmaskM1.a1
|
Description: | The shadowband was intermittently misaligned and not completely masking the sun because
the mirror became loose from the shaft while being polished. The shadowband was realigned
on 1/14 but by 1/27 was again slightly misaligned. The instrument was reoriented with true
north on 1/27 and the shadowband adjusted again on 1/31. The problem was corrected on
2/2 when the mirror mounting was tightened and the shadowband realigned. |
Measurements: | grwtsicldmaskM1.a1: - Cloud decision images, Total Sky Imager, PNG format(png)
grwtsiskycoverM1.b1: - region_sun_count
- count_sub_horz
- region_horizon_count_thin
- region_horizon_count_opaque
- count_mask
- count_thin
- region_sun_count_thin
- region_zenith_count_thin
- region_sun_count_opaque
- Cloud amount, opaque (percent)(percent_opaque)
- count_sky
- Cloud amount, thin (percent)(percent_thin)
- count_sub_proczen
- count_opaque
- region_horizon_count
- count_box
- region_zenith_count
- region_zenith_count_opaque
grwtsiskyimageM1.a1: - JPEG data stream - documentation not yet available
|
Subject: | GRW/TSI/M1 - Contamination of mirror |
DataStreams: | grwtsicldmaskM1.a1, grwtsimovieM1.a1, grwtsiskycoverM1.b1, grwtsiskyimageM1.a1
|
Description: | A persistent, agile bird was landing on top of and polluting the mirror, multiple times
throughout the day, affecting the visible and processed images and cloud fraction data. |
Measurements: | grwtsimovieM1.a1: - MPEG data stream - documentation not yet available
grwtsicldmaskM1.a1: - Cloud decision images, Total Sky Imager, PNG format(png)
grwtsiskycoverM1.b1: - count_sky
- Cloud amount, thin (percent)(percent_thin)
- sun_strength
- count_thin
- count_opaque
- region_zenith_count_thin
- region_zenith_count
- region_zenith_count_opaque
- Cloud amount, opaque (percent)(percent_opaque)
grwtsiskyimageM1.a1: - JPEG data stream - documentation not yet available
|
Subject: | GRW/SKYRAD/M1 - Short direct normal questionable |
DataStreams: | grwskyrad20sM1.a0, grwskyrad60sM1.b1
|
Description: | Starting on 05/08/2010 values of short_direct_normal from the NIP instrument were reading
low (up to 50W/m2). This was most apparent during sunny/partly sunny periods. The
values spontaneously returned to normal on 5/14 with no Ops intervention. Data system checks
after that date revealed no apparent problems with instruments or datalogger. The problem
has not recurred.
Only the short_direct_normal values during this time period are suspect. If direct normal
values are needed they can be re-constructed using the following relationship for each
minute of data:
down_short_hemisp = short_direct_normal * cos(zenith angle) + down_short_diffuse_hemisp |
Measurements: | grwskyrad20sM1.a0:
grwskyrad60sM1.b1: - Radiation, shortwave, direct normal irradiance, 1-min avg(short_direct_normal)
- Shortwave Direct Normal Irradiance, Pyrheliometer, Minima(short_direct_normal_min)
- Shortwave Direct Normal Irradiance, Pyrheliometer, Maxima(short_direct_normal_max)
- short_direct_normal_std
|