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Full catalog/GPM_2AKa
GPM_2AKa·v08·dataset

How much it rained, from radar (GPM, 5 km)

GPM DPR Ka Precipitation Profile 2A 1.5 hours 5 km V08 (GPM_2AKa) at GES DISC
atmosphere NASA GES_DISC Level 2 active
In plain English

What it measures. Rainfall and snowfall estimates measured by radar as it scans down through the atmosphere, at about 5 km spacing, using only the Ka-band radar.

How it's made. Produced by the Ka-band radar of GPM's Dual-Frequency Precipitation Radar, which sends pulses and reads the echoes from raindrops and snowflakes along its path.

How & where you'd use it. Measuring precipitation, especially lighter rain and smaller particles the more sensitive radar can catch; a reliable single-radar product even if the companion radar has issues.

What's measured

ATMOSPHERE › ATMOSPHERIC WATER VAPORATMOSPHERE › PRECIPITATIONSPECTRAL/ENGINEERING › RADAR

Coverage & cadence

  • Time span2014-03-08 → ongoing
  • Measured byGPM (DPR)
  • Processing levelLevel 2
  • Spatial extent-180, -70, 180, 70
  • StatusACTIVE

What you can do with it

  • Map air pollutants — NO₂, aerosols, ozone
  • Track greenhouse gases and Earth's energy budget
  • Feed weather and air-quality analysis
Official description

Version 08 is the current version of the data set. Older versions will no longer be available and have been superseded by Version 08. The 2AKa algorithm provides precipitation estimates from the Ka radar of the Dual-Frequency Precipitation Radar on the core GPM spacecraft. The product contains two swaths of data corresponding to the scans of the Ka radar. The first swath contains matched scans (MS), which are intended to be co-aligned with the Ku-band instantaneous fields of view (IFOV). The second swath contains the high-sensitivity scans (HS), which are interleaved between the Ku/Ka-MS swaths. Both swaths are narrow and centered within the interior of the Ku swath. This is a single-frequency retrieval of precipitation; no information from the Ku radar is used. The retrievals are performed at each radar range bin along the slant path of the radar IFOV for each swath. This is a single-frequency retrieval that relies on Ka-band data only. While the dual-frequency retrieval should give better overall estimates, that algorithm requires co-aligned Ku-band data. This 2AKa product will be produced independently and would not be impacted by any operational issues with the Ku-band radar. The high sensitivity to smaller hydrometeors should result in precipitation estimates in lighter precipitation then the Ku-only data. It is important to note the difference between the single- and the dual-frequency (DF) algorithms. While this 2AKa dataset is a single-frequency retrieval, the DF algorithm employs both KuPR and KaPR L1B standard products as inputs. The DF algorithm cannot be executed unless both L1B products are available. Pixels observed by DPR can be categorized into three types: pixels in the inner swath of normal scans (observed both by KuPR and KaPR), pixels in the outer swath of normal scans (observed only by KuPR), and pixels in the interleaved scans (observed only by KaPR in the high-sensitivity mode). The KuPR algorithm is executed for pixels in both inner and outer swaths of normal scans. The KaPR algorithm is executed for pixels in the inner swath of normal scans and in the interleaved scans. The DF algorithm is executed for pixels of all the three kinds.

Get the data

gpm_2aka_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="GPM_2AKa",
    version="08",
    bounding_box=(-122.5, 37.2, -121.8, 37.9),  # your area (W,S,E,N)
    temporal=("2024-01-01", "2024-12-31"),       # your dates
)
files = earthaccess.open(results)   # stream straight from GES_DISC
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.