Changes for this version include:

• Used PPD flag of ATL03, degraded POD/PPD solutions were flagged and ignored in the ATL08 algorithm.
• To reduce the amount of cloud contamination in the ATL08 signal photons, all photons from 120 m or more above the reference DEM are considered clouds.
• Added a saturation flag to the ATL08 data product that is based on the ATL03 saturation flags. The ATL08 saturation flag indicates that a segment within 100 m is saturated –likely due to water.
• Included a ph_h parameter to the photon group reflecting the height of each photon above the estimated ground surface.
• Changed calculation of absolute canopy heights and height metrics.
• Expanded the canopy height metrics to every 5% ranging from 5 – 95%.
• Removed the Landsat canopy cover check in the algorithm as this check was preventing canopy from being detected in areas with low canopy cover (e.g. savannas) even though reflected photons from woody vegetation are observed at the photon level.
• Changed the search radius parameter from 15 m to 100 m for the initial top of canopy determination in an effort to pull in more, previously missed, top of canopy photons.
• Incorporated the quality_ph flag of the ATL03 product which should exclude many after-pulsing events from the ATL08 algorithm. The after-pulsing events are due to detector saturation and other detector events and over land they occur over water bodies such as wetlands, rivers, etc. This should result in a more accurate surface representation particularly for wetlands where standing water is often found.
• Added the calculation of the photon rates for terrain and canopy points. The addition of these parameters will improve future radiometry studies.