First forest canopy heights from NASA’s ICESat mission

Posted on June 29, 2019June 29, 2019 by Geoff Zeiss

First terrain surface and canopy heights from ICESat-2

Launched in September 2018, ICESat-2 (Ice, Cloud, and land Elevation Satellite-2) has just begun making its first data available. The data map global terrain surface and forest canopies. The Advanced Topographic Laser Altimeter System (ATLAS) instrument on-board ICESat-2 utilizes photon counting technology for the altimetry observations. Photon counting technology is relatively new to the vegetation mapping community. Data from ICESat-2 will provide global terrain elevation and canopy height estimates as well as showing potential for estimation of forest biomass.

The ATL08 land and vegetation product for the ICESat-2 Mission, Amy Neuenschwander, Katherine Pitts Remote Sensing of Environment, 221, February 2019, Pages 247-259 doi/10.1016/j.rse.2018.11.005

Himalayan glaciers lost 28% of ice in last 40 years

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From Our Files

Correlation of temperature and CO2 for last 420,000 years from Vostok

EC Perspective: Accounting for 800,000 years of climate change

Approximately 800,000 years ago something changed in the Earth’s climate system that led to the climate then following a series of approximately 100,000 year cycles. Small, predictable changes in the Earth’s orbit about the Sun act as triggers for the glacial and interglacial periods, but other factors such as ice sheet volume, CO2 concentration, and biological feedback mechanisms are also involved.

Thermokarst distribution in northern circumpolar region

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In this study the global average surface temperature over the past 2 million years has been derived from deep sea cores. The results reveal that global cooling occurred about 300,000 years before the rapid ice sheet growth and the development of the first 100,000-year glacial/deglacial cycle about 800,000 years ago.

Upward revision of methane emissions from shale gas production could erode natural gas’ cleaner energy advantage

Evidence that methane emissions from natural gas production have been considerably underestimated by the EPA was recently reinforced by the initiation of an investigation into how the EPA estimates methane emissions by the EPA’s Inspector General. If it is found that emissions of methane from natural gas production are considerably greater than current estimates, the advantage that natural gas has over coal will be eroded and the advantage of switching to natural gas as a cleaner form of energy diminished.

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