Daily Binned Methyl Chloride Mixing Ratios from Aura Satellite

MLS/Aura satellite data provides daily binned methyl chloride (CH3Cl) mixing ratios on multiple vertical grids. Measurements are derived from the 640 GHz radiometer, with near-global spatial coverage from -82 to +82 degrees latitude. The dataset is produced by the GES DISC and covers the period from August 2, 2004, to the present.

Use Cases

• Analyze lat-lon map vs pressure group data to study the spatial distribution of CH3Cl concentrations in the lower stratosphere.
• Use lat vs pressure zonal mean data to examine meridional gradients and seasonal cycles of methyl chloride.
• Investigate vortex average vs potential temperature data to understand CH3Cl behavior inside the polar vortex.
• Correlate equivalent latitude vs potential temperature zonal mean data with other trace gases to identify transport pathways.
• Utilize the average, min, max, and standard deviation fields within each data group to quantify uncertainty and variability in CH3Cl measurements.

Strengths

• Continuous temporal coverage from August 2004 to present, enabling long-term trend analysis.
• Near-global spatial coverage from -82 to +82 degrees latitude.
• Data provided on multiple vertical grids (e.g., pressure, potential temperature) with associated statistical fields (average, std dev, min, max, rms).

Limitations

• Spatial resolution is 4 degrees latitude by 5 degrees longitude, which is coarse for regional-scale analysis.
• The recommended useful vertical range is limited to between 147 and 4.64 hPa, excluding the troposphere and upper stratosphere.
• Vertical resolution varies from 4-6 km in the lower stratosphere to 8-10 km above 14 hPa, introducing non-uniformity.

Provenance

Source

GES DISC (Goddard Earth Sciences Data and Information Services Center).

Collection Method

Derived from radiances measured by the 640 GHz radiometer on the EOS Aura Microwave Limb Sounder (MLS) satellite instrument.

Time Range

August 2, 2004 to present.

Freshness

Data coverage is stated as 'to current', but specific update frequency is null.

Geography

Near-global, -82 to +82 degrees latitude.