Dataset: ESA Greenhouse Gases Climate Change Initiative (GHG_cci): Column-averaged CH4 Merged Product generated with the EMMA algorithm (CH4_EMMA), version 1.2#
Dataset identifier: esacci.GHG.satellite-orbit-frequency.L2.CH4.TANSO-FTS.GOSAT.EMMA.ch4_v1-2.r1
Data store: cciodp
How to open this dataset in AVL JupyterLab
cciodp_store = new_data_store('cciodp')
ds = cciodp_store.open_data('esacci.GHG.satellite-orbit-frequency.L2.CH4.TANSO-FTS.GOSAT.EMMA.ch4_v1-2.r1')
Bounding box map#
cciodp_store = new_data_store('cciodp')
ds = cciodp_store.open_data('esacci.GHG.satellite-orbit-frequency.L2.CH4.TANSO-FTS.GOSAT.EMMA.ch4_v1-2.r1')
Map tiles and data from OpenStreetMap, under the ODbL.
Basic information#
| Parameter | Value |
|---|---|
| Bounding box longitude (°) | -180.0 to 180.0 |
| Bounding box latitude (°) | -90.0 to 90.0 |
| Time range | 2009-05-31 to 2014-05-30 |
Click here for full dataset metadata.
Variable list#
Click on a variable name to jump to the variable’s full metadata.
| Variable | Long name | Units |
|---|---|---|
| solar_zenith_angle | solar zenith angle | degree |
| sensor_zenith_angle | Sensor zenith angle | degree |
| xch4_quality_flag | quality flag | [none] |
| xch4 | column-average dry-air mole fraction of atmospheric methane in dry air | 1e-9 |
| xch4_uncertainty | 1-sigma uncertainty of the retrieved column-average dry-air mole fraction of atmospheric methane | 1e-9 |
| ch4_profile_apriori | a priori dry-air mole fraction profile of atmospheric methane | 1e-9 |
| pressure_levels | pressure levels | hPa |
| pressure_weight | pressure weight | 1 |
| xch4_averaging_kernel | normalized column averaging kernel | 1 |
| median_processor_id | l2 processor id | [none] |
| median_uncertainty | xch4 median uncertainty | 1e-9 |
| median_uncertainty_se | xch4 median uncertainty se | 1e-9 |
| median_uncertainty_ex | xch4 median uncertainty ex | 1e-9 |
Full variable metadata#
solar_zenith_angle#
| Field | Value |
|---|---|
| standard_name | solar_zenith_angle |
| long_name | solar zenith angle |
| units | degree |
| comment | Solar zenith angle is the the angle between the line of sight to the sun and the local vertical. |
| orig_data_type | float32 |
| fill_value | None |
| size | 297 |
| shape | 297 |
| chunk_sizes | 297 |
| file_chunk_sizes | 297 |
| data_type | float32 |
| dimensions | sounding_dim |
| file_dimensions | sounding_dim |
sensor_zenith_angle#
| Field | Value |
|---|---|
| standard_name | sensor_zenith_angle |
| long_name | Sensor zenith angle |
| units | degree |
| comment | Sensor zenith angle is the angle between the line of sight to the sensor and the local vertical. |
| orig_data_type | float32 |
| fill_value | None |
| size | 297 |
| shape | 297 |
| chunk_sizes | 297 |
| file_chunk_sizes | 297 |
| data_type | float32 |
| dimensions | sounding_dim |
| file_dimensions | sounding_dim |
xch4_quality_flag#
| Field | Value |
|---|---|
| _Unsigned | false |
| long_name | quality flag |
| flag_values | 0, 1 |
| flag_meanings | good_quality potentially_bad_quality |
| comment | 0=good, 1=bad |
| orig_data_type | uint8 |
| fill_value | 65535 |
| size | 297 |
| shape | 297 |
| chunk_sizes | 297 |
| file_chunk_sizes | 297 |
| data_type | uint16 |
| dimensions | sounding_dim |
| file_dimensions | sounding_dim |
xch4#
| Field | Value |
|---|---|
| standard_name | dry_atmosphere_mole_fraction_of_methane |
| long_name | column-average dry-air mole fraction of atmospheric methane in dry air |
| units | 1e-9 |
| comment | Retrieved column-average dry-air mole fraction of atmospheric methane (Xch4) in ppm |
| orig_data_type | float32 |
| fill_value | None |
| size | 297 |
| shape | 297 |
| chunk_sizes | 297 |
| file_chunk_sizes | 297 |
| data_type | float32 |
| dimensions | sounding_dim |
| file_dimensions | sounding_dim |
xch4_uncertainty#
| Field | Value |
|---|---|
| long_name | 1-sigma uncertainty of the retrieved column-average dry-air mole fraction of atmospheric methane |
| units | 1e-9 |
| comment | 1-sigma uncertainty of the retrieved column-average dry-air mole fraction of atmospheric methane (Xch4) in ppm |
| orig_data_type | float32 |
| fill_value | None |
| size | 297 |
| shape | 297 |
| chunk_sizes | 297 |
| file_chunk_sizes | 297 |
| data_type | float32 |
| dimensions | sounding_dim |
| file_dimensions | sounding_dim |
ch4_profile_apriori#
| Field | Value |
|---|---|
| long_name | a priori dry-air mole fraction profile of atmospheric methane |
| units | 1e-9 |
| comment | A priori dry-air mole fraction profile of atmospheric methane in ppm All values represent layer averages within the corresponding pressure levels. Profiles are ordered from surface to top of atmosphere. The a priori profile is needed to apply the Xch4 averaging kernel. See Product Specification Document Version 3 at www.esa-ghg-cci.org for more information. |
| orig_data_type | float32 |
| fill_value | None |
| size | 2970 |
| shape | 297, 10 |
| chunk_sizes | 297, 10 |
| file_chunk_sizes | 297, 10 |
| data_type | float32 |
| dimensions | sounding_dim, layer_dim |
| file_dimensions | sounding_dim, layer_dim |
pressure_levels#
| Field | Value |
|---|---|
| long_name | pressure levels |
| units | hPa |
| comment | Pressure levels define the boundaries of the averaging kernel and mole fraction profile layers. Surface pressure is represented by the 1st element, i.e., profiles are ordered from surface to top of atmosphere. |
| orig_data_type | float32 |
| fill_value | None |
| size | 3267 |
| shape | 297, 11 |
| chunk_sizes | 297, 11 |
| file_chunk_sizes | 297, 11 |
| data_type | float32 |
| dimensions | sounding_dim, level_dim |
| file_dimensions | sounding_dim, level_dim |
pressure_weight#
| Field | Value |
|---|---|
| long_name | pressure weight |
| units | 1 |
| comment | Layer dependent weights needed to apply the averaging kernels (see Product Specification Document Version 3, www.esa-ghg-cci.org) |
| orig_data_type | float32 |
| fill_value | None |
| size | 2970 |
| shape | 297, 10 |
| chunk_sizes | 297, 10 |
| file_chunk_sizes | 297, 10 |
| data_type | float32 |
| dimensions | sounding_dim, layer_dim |
| file_dimensions | sounding_dim, layer_dim |
xch4_averaging_kernel#
| Field | Value |
|---|---|
| long_name | normalized column averaging kernel |
| units | 1 |
| comment | The normalized column-averaging kernel represents the sensitivity of the retrieved Xch4 to the atmospheric methane mole fraction depending on pressure (height). All values represent layer averages within the corresponding pressure levels. Values near one are ideal and indicate that the influence of the a priori is minimal. Profiles are ordered from surface to top of atmosphere. See Product Specification Document Version 3 at www.esa-ghg-cci.org for more information. |
| orig_data_type | float32 |
| fill_value | None |
| size | 2970 |
| shape | 297, 10 |
| chunk_sizes | 297, 10 |
| file_chunk_sizes | 297, 10 |
| data_type | float32 |
| dimensions | sounding_dim, layer_dim |
| file_dimensions | sounding_dim, layer_dim |
median_processor_id#
| Field | Value |
|---|---|
| long_name | l2 processor id |
| comment | ID Institute Algorithm Version |
| 30 SRON RemoTeC-PR v2.3.8 | |
| 31 SRON RemoTeC-FP v2.3.8 | |
| 40 UoL UoL-PR v7.0 | |
| 41 UoL UoL-FP v2.02 | |
| 60 NIES NIES v02.21 | |
| orig_data_type | int16 |
| fill_value | 2147483647 |
| size | 297 |
| shape | 297 |
| chunk_sizes | 297 |
| file_chunk_sizes | 297 |
| data_type | int32 |
| dimensions | sounding_dim |
| file_dimensions | sounding_dim |
median_uncertainty#
| Field | Value |
|---|---|
| long_name | xch4 median uncertainty |
| units | 1e-9 |
| comment | inter-algorithm-spread |
| orig_data_type | float32 |
| fill_value | None |
| size | 297 |
| shape | 297 |
| chunk_sizes | 297 |
| file_chunk_sizes | 297 |
| data_type | float32 |
| dimensions | sounding_dim |
| file_dimensions | sounding_dim |
median_uncertainty_se#
| Field | Value |
|---|---|
| long_name | xch4 median uncertainty se |
| units | 1e-9 |
| comment | standard error of the median uncertainty |
| orig_data_type | float32 |
| fill_value | None |
| size | 297 |
| shape | 297 |
| chunk_sizes | 297 |
| file_chunk_sizes | 297 |
| data_type | float32 |
| dimensions | sounding_dim |
| file_dimensions | sounding_dim |
median_uncertainty_ex#
| Field | Value |
|---|---|
| long_name | xch4 median uncertainty ex |
| units | 1e-9 |
| comment | expected inter-algorithm spread due to measurement noise |
| orig_data_type | float32 |
| fill_value | None |
| size | 297 |
| shape | 297 |
| chunk_sizes | 297 |
| file_chunk_sizes | 297 |
| data_type | float32 |
| dimensions | sounding_dim |
| file_dimensions | sounding_dim |
Full dataset metadata#
| Field | Value |
|---|---|
| title | ESA Greenhouse Gases Climate Change Initiative (GHG_cci): Column-averaged CH4 Merged Product generated with the EMMA algorithm (CH4_EMMA), version 1.2 |
| source | |
| history | |
| references | M. Reuter, H. Bösch, H. Bovensmann, A. Bril, M. Buchwitz, A. Butz, |
| J. P. Burrows, C. W. ODell, S. Guerlet, O. Hasekamp, J. Heymann, N. Kikuchi, | |
| S. Oshchepkov, R. Parker, S. Pfeifer, O. Schneising, T. Yokota, and | |
| Y. Yoshida: A joint effort to deliver satellite retrieved atmospheric ch4 | |
| concentrations for surface flux inversions: the ensemble median algorithm | |
| EMMA. Atmospheric Chemistry and Physics Discussions, 12, 23195-23217, 2012 | |
| product_version | ch4_v1-2 |
| comment | |
| project | |
| ecv | GHG |
| institute | Institute of Environmental Physics |
| processing_level | L2 |
| product_string | EMMA |
| data_type | CH4 |
| sensor_id | TANSO-FTS |
| platform_id | GOSAT |
| abstract | The CH4_EMMA dataset is comprised of level 2, column-averaged dry-air mole fractions (mixing ratios) for methane (XCH4). It has been produced using the ensemble median algorithm EMMA to several different versions of the Japanes Greenhouse gases Observing Satellite (GOSAT) XCH4 data, as part of the ESA Greenhouse Gases Climate Change Initiative (GHG_cci) project. This version of the product is v1.2, and forms part of the Climate Research Data Package 4. The ensemble median algorithm EMMA has been applied to level 2 data of several different retrieval products from the Japanese Greenhouse gases Observing Satellite (GOSAT) This is therefore a merged GOSAT XCH4 Level 2 product, which is primarily used as a comparison tool to assess the level of agreement / disagreement of the various input products (for model-independent global comparison, i.e. for comparisons not restricted to TCCON validation sites and independent of global model data). For further information on the product and the EMMA algorithm please see the EMMA website, the GHG-CCI Data Products webpage or the Product Validation and Intercomparison Report (PVIR). |
| publication_date | 2018-03-19T21:05:17 |
| uuid | 9ed2813d2eda4d958e92ab3ce1ab1fe6 |
| catalog_url | https://catalogue.ceda.ac.uk/uuid/9ed2813d2eda4d958e92ab3ce1ab1fe6 |
| cci_project | GHG |