Chair: TBD
Altimeter measurements of the elevation of the Earth’s ice sheets, glaciers, water bodies and land surface along with the height and vertical structure of vegetation and thickness of sea ice provide foundation data for science and applied purposes. The data is fundamental to understanding, modeling and predicting interactions within and between the solid Earth, hydrosphere, biosphere, cryosphere and atmosphere. The Ice Cloud and land Elevation Satellite (ICESat) mission began comprehensive, global lidar observations of these features, improving significantly upon the resolution and accuracy of spaceflight radar altimeters.
Operating during the period 2003 to 2009, ICESat employed a single-beam approach using a low pulse rate, high pulse energy laser transmitter at 1064 nm and digitization of the analog output from a silicon avalanche photodiode detector. Major accomplishments included monitoring the changing elevation of the Greenland and Antarctic ice sheets and arctic sea ice thickness in response to climate change and providing a global map of biomass stored in forests.
The ICESat-2 mission, launching in 2017, will continue this time-series using a more efficient measurement approach in order to increase the number of beams to six. It will employ a high pulse rate, low pulse energy micropulse laser transmitter at 532 nm and single photon detection using a photomultiplier tube. The increased number of beams will improve spatial and temporal coverage and the accuracy of change measurements. Beyond ICESat-2 the goal is to achieve wide swath lidar mapping, rather than a few profiling beams, with spatial resolution of a few meters thereby greatly expanding the scope of science questions that can be addressed.
This will require a dramatic improvement in measurement efficiency, instrument performance and on-orbit data processing. This session will examine how spaceflight lidar technology has evolved to meet increasingly challenging requirements, in what ways science has been limited by available technology and mission implementations and where critical advances are needed to make the step to next-generation mapping instruments.
In parallel to the above mentioned Lidar instruments, active remote sensing using the conventional Differential Absorption Lidar (DIAL) technique provides a new and sensitive means for the measurement of the climate related atmospheric trace gases with high accuracy from space. Due to the fact that Lidar instruments carry their own light source global observation from space-borne platforms will enable measurements at all latitudes around the globe and during all seasons. From Lidar measurements, complementary information to the current observational system will give new insights into climate feedback from changing wetlands/biomasses and thawing permafrost in the Arctic.
In our session papers are solicited reporting on the status, development and application of new lidar technology and observational methods suited for measurements of the climate related trace gases such as CO2, CH4, N2O, H2O and O3 from space-borne platforms. Also papers on the development, application, and validation of ground-based and airborne greenhouse gas measuring systems serving as so-called pre-cursor experiments or those discussing future combined greenhouse gas observation scenarios with active and passive instruments are involved are also very beneficial for the topic of this session.