GPM
documents
- wikipedia: 日本語 English
- The newest documents are available at: https://www.eorc.jaxa.jp/GPM/archives.html
- Overview of GPM Products Version 2.1 - JAXA/EORC
- GPM利用ハンドブック https://www.eorc.jaxa.jp/TRMM/documents/PR_algorithm_product_information/doc_pr_v8/GPM_data_util_handbook_V6_20181004_J.pdf
- GPM/DPR ATBD (English)
abbreviation 略語
CSF: classification DSD: drop size distribution HS: high sensitivity PIA: path-integrated attenuation PRE: precipitation SLV: solver SRT: surface reference technique VER: vertical
Overview
Change of Ka-radar scan pattern
On May 21, 2018, the scan pattern (incidence angle) of Ka band radar was changed. This is a big change in the observation mode of GPM satellite. You should be careful about this change, if you treat GPM data!
The change process started at scan 3793 of GPMCOR_KAR_1805211531_1704_024020. Scan 3792 was real value but scan 3793 is NULL value (-9999).
The change process completed at scan 741 of GPMCOR_KAR_1805211704_1837_024021. Scan 740 was NULL value (-9999) and scan 741 is a real value.
bands and scan patterns
- Ku band (13.6 GHz) ... similar to TRMM/PR (13.796 GHz and 13.802 GHz). for strong rain. Swath 245 km. N66.28deg~S66.30deg.
- Ka band (35.5 GHz) ... no band in TRMM/PR. for weak rain and snow. Swath 125 km
- after 2018/05/21, Ka band will cover entire swath (245 km)
- local zenith angle (degree) of HS: 8.62, 7.86, 7.11, 6.36, 5.60, 4.85, 4.09, 3.34, 2.58, 1.83, 1.07, 0.32, 0.44, 1.19, 1.95, 2.70, 3.46, 4.21, 4.97, 5.72, 6.48, 7.23, 7.99, 8.74
- local zenith angle (degree) of MS: 9.00, 8.24, 7.49, 6.73, 5.98, 5.22, 4.47, 3.71, 2.96, 2.20, 1.45, 0.69, 0.06, 0.82, 1.57, 2.32, 3.08, 3.83, 4.59, 5.34, 6.10, 6.85, 7.61, 8.37, 9.12
incidence angle (in degree) of GPM DPR (sample statistics from level 2 data); 2019/07/08 Kenlo Nishida KuPR(49) KaPR_MS(25) KaPR_HS(24) ~2018/05/21 KaPR_HS(24) 2018/05/21~ mean stddev step mean stddev step mean stddev mean stddev step 18.186 0.015 9.062 0.017 8.680 0.017 9.760 0.162 17.423 0.014 0.764 8.308 0.019 0.755 7.925 0.008 0.755 10.513 0.184 -0.752 16.667 0.014 0.756 7.556 0.027 0.752 7.174 0.008 0.752 11.271 0.205 -0.758 15.906 0.013 0.761 6.798 0.036 0.758 6.414 0.018 0.760 12.025 0.227 -0.754 15.151 0.012 0.755 6.046 0.045 0.752 5.666 0.028 0.748 12.784 0.249 -0.759 14.391 0.012 0.760 5.292 0.054 0.754 4.911 0.039 0.755 13.535 0.270 -0.752 13.641 0.011 0.750 4.537 0.063 0.756 4.155 0.050 0.756 14.289 0.292 -0.753 12.876 0.010 0.765 3.782 0.072 0.755 3.400 0.061 0.755 15.047 0.313 -0.758 12.120 0.010 0.757 3.030 0.081 0.751 2.650 0.129 0.750 15.809 0.266 -0.762 11.366 0.009 0.753 2.276 0.090 0.755 1.896 0.140 0.754 16.563 0.288 -0.755 10.609 0.009 0.757 1.524 0.099 0.752 1.145 0.151 0.751 17.322 0.309 -0.759 9.852 0.008 0.757 0.769 0.109 0.755 0.388 0.162 0.757 18.078 0.331 -0.756 9.101 0.007 0.751 0.013 0.118 0.757 0.372 0.159 0.016 18.161 0.337 -0.083 8.343 0.007 0.758 0.742 0.103 -0.730 1.125 0.140 -0.754 17.405 0.324 0.756 7.586 0.006 0.757 1.499 0.087 -0.757 1.878 0.122 -0.753 16.648 0.311 0.756 6.835 0.005 0.751 2.245 0.072 -0.746 2.629 0.104 -0.751 15.887 0.298 0.762 6.076 0.005 0.760 3.003 0.057 -0.757 3.386 0.086 -0.757 15.132 0.285 0.755 5.323 0.004 0.752 3.760 0.091 -0.757 4.141 0.068 -0.755 14.373 0.272 0.759 4.567 0.004 0.756 4.512 0.076 -0.753 4.892 0.050 -0.751 13.618 0.259 0.755 3.813 0.003 0.755 5.264 0.060 -0.752 5.644 0.032 -0.751 12.860 0.246 0.757 3.059 0.002 0.754 6.018 0.045 -0.753 6.401 0.015 -0.757 12.107 0.233 0.754 2.305 0.002 0.754 6.774 0.030 -0.757 7.156 0.007 -0.755 11.354 0.220 0.753 1.551 0.001 0.754 7.529 0.016 -0.755 7.908 0.023 -0.752 10.595 0.207 0.758 0.797 0.001 0.754 8.280 0.006 -0.751 8.663 0.041 -0.756 9.842 0.195 0.754 0.046 0.001 0.751 9.034 0.017 -0.754 0.711 0.001 -0.666 1.466 0.001 -0.754 2.219 0.002 -0.753 2.973 0.002 -0.754 3.727 0.003 -0.753 4.481 0.004 -0.754 5.235 0.004 -0.754 5.989 0.005 -0.754 6.747 0.005 -0.758 7.500 0.006 -0.753 8.252 0.007 -0.752 9.010 0.007 -0.758 9.764 0.008 -0.754 10.518 0.008 -0.754 11.274 0.009 -0.757 12.026 0.010 -0.752 12.782 0.010 -0.756 13.547 0.011 -0.764 14.297 0.012 -0.750 15.052 0.012 -0.755 15.809 0.013 -0.757 16.564 0.013 -0.755 17.325 0.014 -0.761 18.082 0.015 -0.757
products
- GPM KuPR L2 Precipitation, V5A or V5B
- V05A: upto 2018/05/21 0138_0311_024011
- V06A: since 2018/05/21 1704_1837_024021
- for land surface study, use Level 2.
- KaHS data is not included in the G-Portal files (instead, filled by NULL value) after the change of scan pattern
G-Portal (2019/07/02) for both Ku and Ka,
V06A: 2014/03/08 ~ 2019/06/30
Download
You can download data from G-portal of JAXA. Use sftp to get large number of files! (You need to set SSH key before it. Check JAXA G-Portal website!)
$ sftp -oPort=2051 [user account]@ftp.gportal.jaxa.jp > mget standard/GPM/GPM.DPR/2A.Ku/05A/2018/??/??/*h5
filename rule
example: GPMCOR_KUR_1501010129_0302_004783_L2S_DU2_05A.h5 example: GPMCOR_DPR_1405281041_1214_001397_L2S_DD2_05A.h5 GPMCOR ... GPM Core satellite (satellite name) KUR ... Ku band radar (sensor name) 140528 ... 2014/05/28 (year/month/day) 1041_1214 ... 10:41 to 12:14 UT (start time ~ end time) 001397 ... orbit number L2S ... Level2 standard DD2 ... algorithm ID 05A ... product version
file structure
V07A.G-Portal
KuPR
- 最初のデータ: 2014/03/08 22:09 GPMCOR_KUR_1403082209_2342_000144_L2S_DU2_07A.h5
- 1ファイルあたり original: 613 MB。digest（下記）: 28 MB
- 全球で1日あたり15.5ファイル。
- 全球で1月あたり465ファイル。
- 全球で1年あたり5660ファイル。
- 全球で2014/03~2023/06 9.3年, 52600ファイル. originalでは32TB
KaPR
- sigmaZeroNPCorrected ... sigma0 corrected for attenuation by the non-precipitation particle
- VER: Vertical Profile Module
- SLV: Solver module
- SRT: surface reference technique (SRT)
陸面解析に不要そうなDatasetを削除して小さなファイルにするスクリプト
#!/usr/bin/python3
import h5py
import sys
# Define source and destination file paths
if len(sys.argv) != 3:
print("Usage: ./GPMKuPR_make_digest.py [source file] [destination file]")
sys.exit(1)
src_file, dst_file = sys.argv[1], sys.argv[2]
# List of datasets to exclude.
# There are 131 datasets in one HDF5 file. If extracted in raw data, their total size is 3103064503 bytes.
# Within them, the following 20 datasets (total size in raw data is 2870594048 bytes; 92.5%) are selected for deleting as a criteria of bigger than 1555456 byte, no flag, no sigmaZero.
exclude_datasets = [
"FS/DSD/binNode",
"FS/DSD/paramRDm",
"FS/DSD/phase",
"FS/PRE/height",
"FS/PRE/zFactorMeasured",
"FS/SLV/epsilon",
"FS/SLV/paramDSD",
"FS/SLV/paramNUBF",
"FS/SLV/precipRate",
"FS/SLV/precipWater",
"FS/SLV/zFactorFinal",
"FS/SRT/PIAalt",
"FS/SRT/PIAweight",
"FS/SRT/RFactorAlt",
"FS/SRT/refScanID",
"FS/SRT/stddevEff",
"FS/VER/airTemperature",
"FS/VER/attenuationNP",
"FS/VER/piaNP",
"FS/VER/piaNPrainFree"
]
# Open source file
src = h5py.File(src_file, 'r')
# Open the destination file
dst = h5py.File(dst_file, 'w')
def copy_item(name, item):
if name in exclude_datasets:
# print (name, " will be excluded!")
return # Skip the excluded datasets
if isinstance(item, h5py.Dataset):
# Copy dataset
dst.create_dataset(name, data=src[name], compression="gzip", compression_opts=9)
elif isinstance(item, h5py.Group):
# Copy group
dst.create_group(name)
# Walk through source file and copy each item to the destination file
src.visititems(copy_item)
# Close the files explicitly
src.close()
dst.close()
V06A.G-Portal
/NS ... KuPR /HS ... KaPR "high-sensitivity" /MS ... KaPR "matched scan" (Same position as KuPR) /NS/PRE/sigmaZeroMeasured ... for land monitoring /NS/PRE/localZenithAngle ... local incident angle /NS/PRE/flagPrecip ... precipitation flag; 0 for no precipitation, 1 for precipitation /NS/PRE/landSurfaceTyp ... ocean mask; 0 - 99 Ocean, 100 - 199 Land, 200 - 299 Coast, 300 - 399 Inland water /NS/FLG/qualityData ... quality flag /NS/Latitude ... latitude /NS/Longitude ... longitude
Keyword(s):
References:[TRMM]