Challenges and Solutions for Frequency and Energy References for Spaceborne and Airborne Integrated Path Differential Absorption Lidars

Andreas Fix,Mathieu Quatrevalet,Christian Büdenbender,Axel Amediek,Gerhard Ehret,Martin Wirth,Benjamin Witschas,B Gross,M Arend,F Moshary

doi:10.1051/epjconf/201611906012

Abstract

The stringent requirements for both the frequency stability and power reference represent a challenging task for Integrated Path Differential Absorption Lidars (IPDA) to measure greenhouse gas columns from satellite or aircraft. Currently, the German-French methane mission MERLIN (Methan Remote Lidar Mission) is prepared. At the same time CHARM-F, an aircraft installed system has been developed at DLR as an airborne demonstrator for a spaceborne greenhouse gas mission. The concepts and realization of these important sub-systems are discussed.

Highlights

The Integrated Path Differential Absorption Lidar (IPDA) technique using hard target reflection in the near IR has the potential to deliver methane and carbon dioxide column measurements from satellite or aircraft with unprecedented accuracy [1]
Carbon dioxide and methane are the two most important anthropogenic greenhouse gases contributing to global radiative forcing and have significantly increased since the beginning of the industrial era
Detailed investigations have been performed on both issues within the development and design phase of CHARM-F and MERLIN

Summary

INTRODUCTION

The Integrated Path Differential Absorption Lidar (IPDA) technique using hard target reflection in the near IR has the potential to deliver methane and carbon dioxide column measurements from satellite or aircraft with unprecedented accuracy [1]. CH4 has an estimated global warming potential per molecule 25 times greater than CO2 over a 100 year horizon and, despite its much lower abundance, is the second most significant anthropogenic greenhouse gas. Large uncertainties in their budget, and feedback mechanisms which are, if at all, only partly understood, limit the accuracy of climate change projections. Wavelength accuracy and energy calibration represent a potential source of systematic error contribution to the measurement of XCH4 and XCO2, the weighted averages of the greenhouse gas dry-air volume mixing ratio which is the primary data product

REQUIREMENTS

ENERGY REFERENCE

FREQUENCY REFERENCE

Findings

CONCLUSIONS