MERRA-2 M2T1NXFLX: Surface Flux Diagnostics V5.12.4

Dataset Availability

1980-01-01T00:00:00Z–2025-07-01T23:00:00Z

Dataset Provider

NASA/MERRA

Earth Engine Snippet

ee.ImageCollection("NASA/GSFC/MERRA/flx/2")

Cadence

1 Hour

Tags

climate merra precipitation sea-salt so2 so4 soil-moisture

Description

M2T1NXFLX (or tavg1_2d_flx_Nx) is an hourly time-averaged data collection in Modern-Era Retrospective analysis for Research and Applications version 2 (MERRA-2). This collection consists of assimilated surface flux diagnostics, such as total precipitation, bias corrected total precipitation, surface air temperature, surface specific humidity, surface wind speed, and evaporation from turbulence. The "surface" in this data collection is the model surface layer. The heights of the model surface layer (HLML) vary with time and location, with the value of ~60 meters above ground. The data field is time-stamped with the central time of an hour starting from 00:30 UTC, e.g.: 00:30, 01:30, ... , 23:30 UTC.

MERRA-2 is the latest version of global atmospheric reanalysis for the satellite era produced by NASA Global Modeling and Assimilation Office (GMAO) using the Goddard Earth Observing System Model (GEOS) version 5.12.4. The dataset covers the period of 1980-present with the latency of ~3 weeks after the end of a month.

Bands

Pixel Size
69375 meters

Y Pixel Size
55000 meters

Bands

Name	Units	Min	Max	Pixel Size	Description
BSTAR	m/s^2	-0.021035*	0.791739*	meters	Surface buoyancy scale
CDH	kg/m^2/s	8e-06*	0.522482*	meters	Surface exchange coefficient for heat
CDM	kg/m^2/s	5e-06*	0.518079*	meters	Surface exchange coefficient for momentum
CDQ	kg/m^2/s	8e-06*	0.522482*	meters	Surface exchange coefficient for moisture
CN		0.000646*	0.032227*	meters	Surface neutral drag coefficient
DISPH	m	0*	23.0781*	meters	Zero plane displacement height
EFLUX	W/m^2	-308.949*	1655.85*	meters	Total latent energy flux
EVAP	kg/m^2/s	-0.00011*	0.000673*	meters	Evaporation from turbulence
FRCAN		0*	1*	meters	Areal fraction of anvil showers
FRCCN		0*	0.423096*	meters	Areal fraction of convective showers
FRCLS		0*	1*	meters	Areal fraction of nonanvil large scale showers
FRSEAICE		0*	1*	meters	Ice covered fraction of tile
GHTSKIN	W/m^2	-245.078*	1e+15*	meters	Ground heating for skin temperature
HFLUX	W/m^2	-1181.24*	686.742*	meters	Sensible heat flux from turbulence
HLML	m	42.3642*	71.0599*	meters	Surface layer height
NIRDF	W/m^2	0*	282.495*	meters	Surface downwelling nearinfrared diffuse flux
NIRDR	W/m^2	0*	592.217*	meters	Surface downwelling nearinfrared beam flux
PBLH	m	42.3621*	5780.88*	meters	Planetary boundary layer height
PGENTOT	kg/m^2/s	0*	0.017593*	meters	Total column production of precipitation
PRECANV	kg/m^2/s	0*	0.000968*	meters	Anvil precipitation
PRECCON	kg/m^2/s	0*	0.002629*	meters	Convective precipitation
PRECLSC	kg/m^2/s	0*	0.014614*	meters	Nonanvil large scale precipitation
PRECSNO	kg/m^2/s	0*	0.006308*	meters	Snowfall
PRECTOTCORR	kg/m^2/s	0*	0.110565*	meters	Total precipitation
PRECTOT	kg/m^2/s	0*	0.017509*	meters	Total precipitation
PREVTOT	kg/m^2/s	0*	0.001474*	meters	Total column re-evaporation/sublimation of precipitation
QLML		0*	0.034333*	meters	Surface specific humidity
QSH	Mass fraction	0*	0.044069*	meters	Effective surface specific humidity
QSTAR	Mass fraction	-0.000139*	0.005463*	meters	Surface moisture scale
RHOA	kg/m^3	0.658498*	1.68283*	meters	Air density at surface
RISFC		-318.273*	578.05*	meters	Surface bulk Richardson number
SPEEDMAX	m/s	0.074227*	49.4767*	meters	Surface wind speed
SPEED	m/s	0.061141*	49.3541*	meters	Surface wind speed
TAUGWX	N/m^2	-3.06294*	5.8716*	meters	Surface eastward gravity wave stress
TAUGWY	N/m^2	-5.10649*	4.99554*	meters	Surface northward gravity wave stress
TAUX	N/m^2	-5.48865*	5.09378*	meters	Eastward surface stress
TAUY	N/m^2	-6.19036*	4.19191*	meters	Northward surface stress
TCZPBL	m	6.55864*	2.83712e+06*	meters	Transcom planetary boundary layer height
TLML	K	191.833*	320.174*	meters	Surface air temperature
TSH	K	185.73*	328.859*	meters	Effective surface skin temperature
TSTAR	K	-11.0761*	5.74402*	meters	Surface temperature scale
ULML	m/s	-48.8082*	42.8239*	meters	Surface eastward wind
USTAR	m/s	0.000667*	2.31844*	meters	Surface velocity scale
VLML	m/s	-41.9408*	44.3777*	meters	Surface northward wind
Z0H	m	1e-05*	4.54622*	meters	Surface roughness for heat
Z0M	m	1e-05*	4.54622*	meters	Surface roughness

* estimated min or max value

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Terms of Use

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Code Editor (JavaScript)

var dataset = ee.ImageCollection('NASA/GSFC/MERRA/flx/2')
                  .filter(ee.Filter.date('2022-02-01', '2022-02-02'));
var surface_buoyancy_scale = dataset.select('BSTAR');
var sbsVis = {
  min: -0.00998,
  max: 0.01174,
  palette: ['001137', '01abab', 'e7eb05', '620500']
};
Map.setCenter(-95, 39, 2);
Map.addLayer(surface_buoyancy_scale, sbsVis, 'Surface buoyancy scale');

Open in Code Editor

MERRA-2 M2T1NXFLX: Surface Flux Diagnostics V5.12.4

M2T1NXFLX (or tavg1_2d_flx_Nx) is an hourly time-averaged data collection in Modern-Era Retrospective analysis for Research and Applications version 2 (MERRA-2). This collection consists of assimilated surface flux diagnostics, such as total precipitation, bias corrected total precipitation, surface air temperature, surface specific humidity, surface wind speed, and evaporation from turbulence. The …

NASA/GSFC/MERRA/flx/2, climate,merra,precipitation,sea-salt,so2,so4,soil-moisture

1980-01-01T00:00:00Z/2025-07-01T23:00:00Z

-90 -180 90 180

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https://developers.google.com/earth-engine/datasets