GLMETRICS Mean Ground Elevation layer, acquired over Bowie, Maryland in June 2012.

View full-size imageGoddard’s LiDAR, Hyperspectral, and Thermal Imager (G-LiHT) mission is a portable, airborne imaging system that aims to simultaneously map the composition, structure, and function of terrestrial ecosystems. G-LiHT primarily focuses on a broad diversity of forest communities and ecoregions in North America, mapping aerial swaths over the conterminous United States (CONUS), Alaska, Puerto Rico, and Mexico.

The purpose of G-LiHT’s Metrics data product (GLMETRICS) is to provide extensive lidar height and density metrics and return statistics in more than 80 science dataset layers. Included in the product are mean, standard deviation, and percentile information for ground, tree, and shrub data. Some flights also contain Canopy Height Model (CHM) and Digital Terrain Model (DTM) returns. The total number of metrics layers varies by flight or campaign.

GLMETRICS data are processed as a raster data product (GeoTIFF) at a 13 meter spatial resolution over locally defined areas.

Characteristic | Description |
---|---|

Collection | G-LiHT |

DOI | 10.5067/Community/GLIHT/GLMETRICS.001 |

File Size | ~1 MB |

Temporal Resolution | Varies |

Temporal Extent | 2011-06-30 to Present |

Spatial Extent | North America |

Coordinate System | Universal Transverse Mercator (UTM) |

Datum | World Geodetic System (WGS84) |

File Format | GeoTIFF |

Geographic Dimensions | Varies |

Characteristic | Description |
---|---|

Number of Science Dataset (SDS) Layers | 88 |

Columns/Rows | Varies x Varies |

Pixel Size | 13 m |

SDS Name | Description | Units | Data Type | Fill Value | No Data Value | Valid Range | Scale Factor |
---|---|---|---|---|---|---|---|

pulse_density | Laser pulse density | Number | 32-bit floating point | N/A | N/A | N/A | N/A |

pulse_scan_angle | Mean laser pulse scan angle (from nadir) | Degree | 32-bit floating point | N/A | N/A | N/A | N/A |

returns_per_pulse | Mean number of returns per laser pulse | Number | 32-bit floating point | N/A | N/A | N/A | N/A |

all_mean | Mean of all return heights | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

all_qmean | Quadratic mean of all return heights | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

all_stdev | Standard deviation of all return heights | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

all_skew | Skewness of all return heights | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

all_kurt | Kurtosis of all return height | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

all_p10 | Height percentiles (10% increment) of all returns | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

all_p20 | Height percentiles (20% increment) of all returns | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

all_p30 | Height percentiles (30% increment) of all returns | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

all_p40 | Height percentiles (40% increment) of all returns | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

all_p50 | Height percentiles (50% increment) of all returns | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

all_p60 | Height percentiles (60% increment) of all returns | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

all_p70 | Height percentiles (70% increment) of all returns | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

all_p80 | Height percentiles (80% increment) of all returns | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

all_p90 | Height percentiles (90% increment) of all returns | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

all_p100 | Height percentiles (100% increment) of all returns | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

all_d0 | Density deciles (0% increment) of all returns | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

all_d1 | Density deciles (10% increment) of all returns | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

all_d2 | Density deciles (20% increment) of all returns | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

all_d3 | Density deciles (30% increment) of all returns | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

all_d4 | Density deciles (40% increment) of all returns | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

all_d5 | Density deciles (50% increment) of all returns | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

all_d6 | Density deciles (60% increment) of all returns | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

all_d7 | Density deciles (70% increment) of all returns | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

all_d8 | Density deciles (80% increment) of all returns | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

all_d9 | Density deciles (90% increment) of all returns | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

all_refl_max | Maximum relative reflectance of all single returns | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

all_refl_mean | Mean relative reflectance of all single returns | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

shrub_mean | Mean of shrub return heights | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

shrub_stdev | Standard deviation of shrub return heights | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

shrub_refl_max | Maximum relative reflectance of shrub single returns | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

shrub_refl_mean | Mean relative reflectance of shrub single returns | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_mean | Mean of tree return heights | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_qmean | Quadratic mean of tree return heights | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_stdev | Standard deviation of tree return height | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_rugosity | Standard deviation of gridded CHM values | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_skew | Skewness of tree return heights | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_kurt | Kurtosis of tree return height | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_fcover | Fraction of first returns intercepted by tree | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_fract_all | Fraction of all returns classified as tree | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_p10 | Height percentiles (10% increment) of tree return | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_p20 | Height percentiles (20% increment) of tree return | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_p30 | Height percentiles (30% increment) of tree return | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_p40 | Height percentiles (40% increment) of tree return | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_p50 | Height percentiles (50% increment) of tree return | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_p60 | Height percentiles (60% increment) of tree return | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_p70 | Height percentiles (70% increment) of tree return | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_p80 | Height percentiles (80% increment) of tree return | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_p90 | Height percentiles (90% increment) of tree return | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_p100 | Height percentiles (100% increment) of tree return | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_d0 | Density deciles (0% increment) of tree return | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_d1 | Density deciles (10% increment) of tree return | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_d2 | Density deciles (20% increment) of tree return | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_d3 | Density deciles (30% increment) of tree return | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_d4 | Density deciles (40% increment) of tree return | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_d5 | Density deciles (50% increment) of tree return | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_d6 | Density deciles (60% increment) of tree return | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_d7 | Density deciles (70% increment) of tree return | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_d8 | Density deciles (80% increment) of tree return | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_d9 | Density deciles (90% increment) of tree return | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_iqr | Interquartile range (tree_p75‐tree_p25) of tree returns | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_vdr | Vertical Distribution Ratio (normalized height range between canopy top and median tree returns) | N/A | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_mad | Median Absolute Deviation (MAD = median(|height - median height|) of tree returns | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_aad | Mean Absolute Deviation (AAD = mean(|height ‐ mean height|) of tree returns | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_crr | Canopy Relief Ratio (CRR = mean-min:max-min) of tree returns | N/A | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_refl_max | Maximum relative reflectance of tree single returns | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

tree_refl_mean | Mean relative reflectance of tree single returns | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

ground_elev_mean | Mean of ground return elevations | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

ground_slope | Mean slope derived from gridded DTM | Degree | 32-bit floating point | N/A | N/A | N/A | N/A |

ground_aspect | Aspect derived from gridded DTM | Degree | 32-bit floating point | N/A | N/A | N/A | N/A |

ground_refl_max | Maximum relative reflectance of ground single returns | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

ground_refl_mean | Mean relative reflectance of ground single returns | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

nmbu_tree_d0 | Density deciles (0% increment) of tree return | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

nmbu_tree_d1 | Density deciles (10% increment) of tree return | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

nmbu_tree_d2 | Density deciles (20% increment) of tree return | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

nmbu_tree_d3 | Density deciles (30% increment) of tree return | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

nmbu_tree_d4 | Density deciles (40% increment) of tree return | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

nmbu_tree_d5 | Density deciles (50% increment) of tree return | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

nmbu_tree_d6 | Density deciles (60% increment) of tree return | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

nmbu_tree_d7 | Density deciles (70% increment) of tree return | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

nmbu_tree_d8 | Density deciles (80% increment) of tree return | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

nmbu_tree_d9 | Density deciles (90% increment) of tree return | Fraction | 32-bit floating point | N/A | N/A | N/A | N/A |

dsm_rugosity | Digital Surface Model Rugosity | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

dsm_mean | Digital Surface Model Mean | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

chm_rugosity | Canopy Height Model Rugosity | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

chm_mean | Canopy Height Model Mean | Meters | 32-bit floating point | N/A | N/A | N/A | N/A |

Information for the GLMETRICS product can be found on the G-LiHT website.

Science Data Layers do not currently reflect valid Fill Value, No Data Value, Valid Range, or Scaling Factor. These will be updated when more information is available.