**Data Format Structure for 2A25, PR Rainfall Rate and Profile ** |

Name | Type | Record Size (byte) | Dim Size/ # of Records | Scaled by | Range | Unit | Description |

ECS Core Metadata | Char Attribute | 10,000 | - | - | - | - | ECS Core Metadata. |

PS Metadata | Char Attribute | 10,000 | - | - | - | - | Product Specific Metadata. |

Clutter Flag | Vdata Table | 4 | 49 | - | - | - | Mainlobe Clutter Edge and Sidelobe Clutter Range. ( detail ) |

Swath Structure | Char Attribute | 5,000 | - | - | - | - | Specification of the swath geometry. |

Scan Time | Vdata Table | 8 | nscan | - | - | - | Time associated with the scan, expressed as 8-byte float UTC second of the day. |

Latitude | Float SDS | 4 | nray*nscan | - | - | degree | Earth location of the center of the IFOV at the altitude of the earth ellipsoid. The first dimension is latitude and longitude, in that order. The next dimensions are numbers of pixels and scans. |

Longitude | Float SDS | 4 | nray*nscan | - | - | degree | Earth location of the center of the IFOV at the altitude of the earth ellipsoid. The first dimension is latitude and longitude, in that order. The next dimensions are numbers of pixels and scans. |

scLocalZenith | Float SDS | 4 | nray*nscan | - | - | degree | Spacecraft local zenith angle. |

Scan Status | Vdata Table | 15 | nscan | - | - | - | Status of each scan. |

Navigation | Vdata Table | 88 | nscan | - | - | - | Spacecraft geocentric information. |

Rain Rate | Integer SDS | 2 | 80*nray*nscan | 100 | 0.0 ~ 300.0 | mm/h | Estimate of rain rate at the radar range gates from 0 to 20 km along the slant range. A value of -88.88 mm/hr (stored as -889) means ground clutter. |

Reliability | Integer SDS | 1 | 80*nray*nscan | - | 0 ~ 255 | - | For estimated rain rates at the radar range gates from 0 to 20km. ( Bit and Meaning ) |

Corrected Z-factor | Integer SDS | 2 | 80*nray*nscan | 100 | 0.0 ~ 80.0 | dBZ | Attenuation corrected reflectivity factor (Z) at the radar range gates from 0 to 20 km along the slant range. Values of reflectivity less than 0.0 dBZ are set to 0.0 dBZ. A value of -88.88 dB (stored as -8888) is a ground clutter flag, -9999 is for missing data in reflectivity profile. |

Parameter Node | Integer SDS | 2 | 5*nray*nscan | - | 0 ~ 79 | - | Range bin numbers of the nodes at which the values of Attenuation and Z-R Parameters are given (see below). The values of the parameters between the nodes are linearly interpolated. |

Attenuation Parameter Alpha | Float SDS | 4 | 5*nray*nscan | - | 0.00010 ~ 0.00200 | - | It relates the attenuation coefficient, k (dB/km) to the Z-factor: k = α^{β}. α is computed at ncell2(5) radar range gates for each ray. |

Attenuation Parameter Beta | Float SDS | 4 | nray*nscan | - | 0.5 ~ 2.0 | - | It relates the attenuation coefficient, k (dB/km) to the Z-factor: k = α*Z^{β}. β is computed for each ray. |

Z-R Parameter a | Float SDS | 4 | 5*nray*nscan | - | 0.0050 ~ 0.2000 | - | Parameter a for Z-R relationship (R=aZ^{b}) is determined from the rain type and the height relative to the freezing level, the non-uniformity parameter (ζ) and the correction factor (ε) for the surface reference technique. |

Z-R Parameter b | Float SDS | 4 | 5*nray*nscan | - | 0.500 ~ 1.000 | - | Parameter a for Z-R relationship (R=aZ^{b}) is determined from the rain type and the height relative to the freezing level, the non-uniformity parameter (ζ) and the correction factor (ε) for the surface reference technique. |

Precipitation Water Parameter A | Float SDS | 4 | 5*nray*nscan | - | - | - | Parameter A in the M = AZ^B relationship. |

Precipitation Water Parameter B | Float SDS | 4 | 5*nray*nscan | - | - | - | Parameter B in the M = AZ^B relationship. |

Precipitation Water Parameter Sum | Float SDS | 4 | 2*nray*nscan | - | - | - | Vertically integrated value of sum precipitation water content calculated from Ze at each range bin. The first index is the precipitation liquid water content from the freezing height to the actual surface. The second index is the sum of precipitation ice content from the top of the storm to the freezing height. Units are gkm/m3(kg/m2) and it ranges from 0.0 to 50.0. |

Maximum Z | Float SDS | 4 | nray*nscan | - | 0.0 ~ 100.0 | dBZ | Maximum value of measured reflectivity factor at each IFOV. |

Rain Flag | Integer SDS | 2 | nray*nscan | - | - | - | Rain Flag indicates rain or no rain status and the rain type assumed in rain rate retrieval. The default value is 0 (no rain). Bit 0 is the least significant bit (i.e., if bit i=1 and other bits =0, the unsigned integer value is 2**i). |

Rain Type | Integer SDS | 2 | nray*nscan | - | - | - | A copy of the 2A23 Rain Type field. See 2A23 description. |

Range Bin Numbers | Integer SDS | 2 | 5*nray*nscan | - | 0 ~ 79 | - | Range Bin Number of various quantities for each ray in every scan. The Range Bin Numbers in this algorithm are different from the NASDA definition of Range Bin Number described in the ICS, Volume 3. The Range Bin Numbers in the algorithm range from 0 to 79 and have an interval of 250m. The earth ellipsoid is defined as range bin 79. |

Averaged Rain Rate | Float SDS | 4 | 2*nray*nscan | - | (1)0.0 ~ 3000.0 (2)0.0 ~ 300.0 | mm/h | There are two kinds of Average Rain Rate. The first one is the average rain rate for each ray between the two predefined heights of 2 and 4 km. The second one is the integral of rain rate from rain top to rain bottom. |

Precipitable Water Sum | Float SDS | 4 | 2*nray*nscan | - | - | - | Vertically integrated value of sum precipitation water content calculated from Ze at each range bin. The first index is the precipitation liquid water content from the freezing height to the actual surface. The second index is the sum of precipitation ice content from the top of the storm to the freezing height. Units are gkm/m3(kg/m2) and it ranges from 0.0 to 50.0. |

Method Flag | Integer SDS | 2 | nray*nscan | - | - | - | Method Flag indicates which method is used to derive the rain rate. The default value is 0 (including no rain case). Bit 0 is the least significant bit (i.e., if bit i =1 and other bits =0, the unsigned integer value is 2**i). |

Epsilon | Float SDS | 4 | nray*nscan | - | 0.0 ~ 100.0 | - | Correction factor for the surface reference. |

Epsilon_0 | Float SDS | 4 | nray*nscan | - | 0.0 ~ 100.0 | - | The adjustment parameter computed from the filtered surface reference PIA (2A21 algorithm). |

Zeta | Float SDS | 4 | 2*nray*nscan | - | 0.0 ~ 100.0 | - | Roughly represents the rain rate integrated along the ray using two different methods. |

Zeta_mn | Float SDS | 4 | 2*nray*nscan | - | 0.0 ~ 100.0 | - | Average of zeta in the vicinity of each beam position (average over three scans and three IFOVs). It is calculated using two methods. |

Zeta_sd | Float SDS | 4 | 2*nray*nscan | - | 0.0 ~ 100.0 | - | Standard deviation of zeta in the vicinity of each beam position (using three scans and three IFOVs). It is calculated using two methods. |

Xi | Float SDS | 4 | 2*nray*nscan | - | 0.0 ~ 99.0 | - | Normalized standard deviation defined as Zeta_sd/Zeta_mn. When Zeta_mn takes on small values (or zero) Xi is set to 99.0. It is calculated using two methods. |

NUBF Correction Factor | Float SDS | 4 | 3*nray*nscan | - | 1 ~ 10 | - | The Non-Uniform Beam Filling (NUBF) Correction Factor is used as a correction to reflectivity and attenuation calculations. It’s range is between 1.0 and 10.0 and is unitless. The dimension of 3 has the following meanings (in C): 0 NUBF correction factor for the surface reference 1 NUBF correction factor for the R-Ze relation 2 NUBF correction factor for the LWC-Ze relation Note that the NUBF correction factor for the k-Ze relation is stored in epsilon nubf. |

Quality Flag | Integer SDS | 2 | nray*nscan | - | 0 ~ 32767 | - | The default value is 0 (normal). Bit 0 is the least significant bit (i.e., if bit i =1 and other bits =0, the unsigned integer value is 2**i). The following meanings are assigned to each bit in the 16-bit integer if the bit = 1. 0: normal +1: unusual situation in rain average +2: NSD of zeta (xi) calculated from less than 6 points +4: NSD of PIA calculated from less than 6 points +8: NUBF for Z-R below lower bound +16: NUBF for PIA above upper bound +32: epsilon not reliable, epsi\_sig less than or equal to 0.0 +64: 2A21 input data not reliable +128: 2A23 input data not reliable +256: range bin error +512: sidelobe clutter removal +1024: probability=0 for all tau +2048: pia\_surf\_ex less than or equal to 0.0 +4096: const Z is invalid +8192: reliabFactor in 2A21 is NaN +16384: data missing |

Near Surface Rain | Float SDS | 4 | nray*nscan | - | 0 ~ 3000 | mm/hr | Rainfall rate near the surface. A value of -99.99 mm/hr is a missing flag. |

Near Surface Z | Float SDS | 4 | nray*nscan | - | 0.0 ~ 100.0 | dBZ | Reflectivity near the surface. A value of -99.99 dBZ is a missing flag. |

Estimated Surface Rain | Float SDS | 4 | nray*nscan | - | 0 ~ 3000 | mm/hr | Reflectivity near the surface. A value of -99.99 mm/hr is a missing flag. |

PIA | Float SDS | 4 | 3nray*nscan | - | - | - | Path Integrated Attenuation (PIA)[two-way] estimates for three cases: (1) The final adjusted PIA estimate (2) The difference between the PIA at the surface and near surface range bins (3) The PIA estimate from 2A21 |

Error Rain | Float SDS | 4 | nray*nscan | - | - | dB | Error in Near Surface Rain Rate. |

Error Z | Float SDS | 4 | nray*nscan | - | 0.0 ~ 100.0 | dBZ | Error in Near Surface Z. |

Spares | Float SDS | 4 | 2*nray*nscan | - | - | - | Contents and ranges are not public. |

Height of Freezing Level | Float SDS | 4 | nray*nscan | - | - | m | A positive Height of Freezing Level is the height of the 0°C isotherm above mean sea level in meters. estimated from climatological surface temperature data. Negative values are defined as: -5555: When error occurred in the estimation of Height of Freezing Level -8888: No rain -9999: Data missing |

Sigma-zero | Float SDS | 4 | nray*nscan | - | -50.00 ~ 20.00 | dB | The normalized surface cross section. This field is copied from the 2A21 product file. |