Strong Release of Methane on Mars in Northern Summer 2003

Abstract

Living systems produce more than 90% of Earth's atmospheric methane; the balance is of geochemical origin. On Mars, methane could be a signature of either origin. Using high-dispersion infrared spectrometers at three ground-based telescopes, we measured methane and water vapor simultaneously on Mars over several longitude intervals in northern early and late summer in 2003 and near the vernal equinox in 2006. When present, methane occurred in extended plumes, and the maxima of latitudinal profiles imply that the methane was released from discrete regions. In northern midsummer, the principal plume contained approximately 19,000 metric tons of methane, and the estimated source strength (>/=0.6 kilogram per second) was comparable to that of the massive hydrocarbon seep at Coal Oil Point in Santa Barbara, California.

NOMAD, an Integrated Suite of Three Spectrometers for the ExoMars Trace Gas Mission: Technical Description, Science Objectives and Expected Performance

“…The reports of methane observations from ground-based observatories (Krasnopolsky et al 2004;Mumma et al 2009), from space-borne instruments (Fonti and Marzo 2010;Geminale et al 2011), and in-situ (Webster et al 2015) pose fundamental challenges to our understanding of the chemistry taking place in the Martian atmosphere (Zahnle et al 2011). These studies showed high spatial and temporal variability, which cannot immediately be explained by models (Lefèvre and Forget 2009).…”

“…Standard photochemical models (Summers et al 2002) predict a lifetime for methane of 300 years, which is much longer than the mixing timescales in the atmosphere and so would imply a uniformly distributed methane in the atmosphere and no seasonal effects. Especially the data measured in (Mumma et al 2009) indicate that the lifetime should be much shorter (Holmes et al 2015), perhaps as short as 200 days. The recent observations by the Mars Science Laboratory (MSL) at Gale Crater indicate a background level of 0.2-0.8 ppb (parts per billion), showing a seasonal pattern, and localized pulses of CH 4 reaching 10 ppb (Webster et al 2013(Webster et al , 2015.…”

“…It controls the stability of the atmosphere, dominates the atmospheric chemistry, and has a radiative impact through , Krasnopolsky et al (2004), Mumma et al (2009). b , Smith (2004), Smith et al (2009a).…”

A hollow-waveguide gas correlation radiometer for ultra-precise column measurements of formaldehyde on Mars

“…In 2004, Wong et al [8] gave photochemical lifetimes for CH4 and CH2O of 670 years and 7.5 hours respectively. In 2009, Mumma et al [9] compared observed measurements of methane in spring 2006 with the amount of methane released in a plume observed in March 2003 and found the 2006 mixing ratios to contradict with the estimated lifetime for methane. They concluded that a process other than photochemical destruction must be responsible for the majority of the methane removal and found the destruction lifetime of methane to range from -0.6 to -4 Earth years depending on whether the large release was a onetime, or annually occurring event.…”

Planetary science: A whiff of mystery on Mars

“…In January 2009, the leader of one of the teams, Michael Mumma from NASA's Goddard Space Flight Center in Greenbelt, Maryland, published a paper 4 Lefèvre calculated that the atmospheric lifetime of methane is less than 200 days 5 hundreds of times shorter than prevailing models of Mars's atmosphere predict. "If the measurements are correct, this means that we are missing something really important, " says Lefèvre.…”