Science Objectives


  1. Geographical extent and temporal persistence of the urban plume:
    • First characterization of regional air quality
    • Comparisons to background air
    • Unique chemical signatures?

  2. Regional oxidants production:
    • O3, peroxides, acids, radicals
    • Alterations of photochemistry by aerosol heterogeneous and radiative processes

  3. Hydrocarbon oxidation products:
    • Evolution of long-lived intermediates, e.g. acetone
    • Impacts on regional HOx and NOx partitioning and budgets
    • Secondary organic aerosol formation
    • Removal mechanisms

  4. Reactive nitrogen:
    • Lifetime of NOx
    • Differential fate of reservoirs:
      1. HNO3-soluble, sensitive to aerosols and clouds
      2. PANs-thermally decomposed, sensitive to temperature
      3. Alkyl nitrates - long-lived, potentially important to global NOx

  5. Gas-aerosol chemical processes:
    • New particle formation
    • Condensation from gas phase
    • Oxidation
    • Microphysical properties, effects on clouds
    • Feedbacks on gas phase (removal, photolysis)

  6. Aerosol radiative properties:
    • Evolution of optical properties, absorption vs. scattering
    • Internal vs. external mixture
    • Vertical radiation profiles

  7. Regional surface-atmosphere interactions:
    • Background air composition
    • Urban plume + fire emissions
    • Urban plume + biogenic emissions

Reasons to Study Mexico City Outflow:

mexico city pollution