This project develops a high precision and fast tunable laser technology for Earth and planetary Science missions to measure atmospheric constituents (such as CO2, methane, and CO) and parameters (such as surface pressure and wind velocities). CO2, methane, and CO are significant greenhouse trace gases. Missions to globally measure these gases are recommended in the NRC Decadal Survey to close the carbon budget. Our technology overcomes major problems with current state of the art and enables critical capabilities for these decadal missions and similar missions on alternative platforms, such as the Global Hawk UAV or the International Space Station. To meet the unprecedented precision targets of these missions, pulsed lidar sounding techniques are being developed to measure the two-way absorption spectra of target species from the spacecraft to the surface and back. The proposed technology can be readily applied to other wavelengths for other species. The proposed work will result in a novel transmitter technology that can: Significantly lower cost (by >50%), size, mass, and power consumption of the transmitter; scan an arbitrary number of programmable wavelengths and even multiple species/lines with a single tunable laser, which is not possible with existing technologies; improve the transmitter reliability by reducing parts counts and gas cell instability; improve the measurement precision by eliminating unwanted spectral crosstalk; leverage mature technologies/Telcordia qualified components to accelerate the TRL.