Correlation coefficient and ratio of dissolved black carbon to water-soluble organic carbon are relatively high for biomass burning aerosols

Atmospheric deposition flux of dissolved black carbon to the ocean is mainly contributed by biomass burning aerosols

The dissolved black carbon in aerosols has less condensed aromatic structures than the major rivers of the world

Tropical upward ozone flux compensates ∼35% of extratropical downward ozone flux, which cannot be neglected for ozone stratosphere-troposphere exchange (STE)

The global ozone STE averaged over 2007-2010 is 347±12 Tg year^-1 from two reanalyses and observations, which should be used to constrain the tropospheric ozone budget

Cloud radiative effects enhance both extratropical downward flux and tropical upward flux based on observations, increasing global ozone STE by ∼25%

The chemical formation of particulate nitrate (pNO3-) at the surface layer cannot explain the daytime variation of pNO3-

The residual layer entrainment is an important process for surface pNO₃^- enhancement in the early morning

HNO₃ production is less efficient throughout the boundary layer than what is observed in the surface layer in the afternoon

Atmospheric ozone sensitivity to solar proton events is derived from multiple satellites and the WACCM-D model

A good agreement exists between nighttime data sets. For daytime, there is agreement only when largest, major SPEs are included

Our results indicate that WACCM-D provides a realistic and/or conservative estimate of ozone sensitivity

The vertical reflection of gravity waves at the low-latitude tropopause is significantly stronger in the northern hemisphere

The southern hemisphere appears more conducive to the gravity-wave propagation from the troposphere to the mesosphere in summer and winter

There is an upper limit in the horizontal wavelength relative to the phase speed for gravity waves to reach the upper mesosphere

Recoil leaders main source of fast processes in negative lightning

Recoil leaders initiate in bidirectional manner

Mixed mode pulses connect directly to structure

Sea breezes play a distinct role in the distribution of primary and secondary pollution throughout the urban Boston area

Steep spatial gradients in secondary pollution occur during sea breezes, posing a challenge to traditional air monitoring networks

The sea breeze also presents unique challenges in long-term averages of air quality derived from satellite instruments

With increasing PM_2.5, summer UHII weakens and winter UHII strengthens

Winter PM_2.5 pollution weakens the UHII at night but strengthens it during daytime

PM_2.5 affects UHII via aerosol-radiation interaction in summer and via aerosol-PBL interaction in winter

Satellite observations of NH3 from 2 sensors (IASI, CrIS) are used to estimate UK NH3 emissions in Mar-Sep at fine scales (10 km, monthly)

Satellite-derived NH3 emissions total 272 Gg from IASI and 389 Gg from CrIS and exhibit a spring (April) and summer (July) peak

Bottom-up emissions used for research and policy are 27-49% less than the satellite-derived estimates and miss the summer emissions peak

A hindcast of the 2018/19 stratospheric sudden warming was performed using a gravity-wave permitting high-top general circulation model

Planetary waves excited by gravity wave forcing cause the formation of a mesospheric inversion layer

Both planetary wave and gravity wave forcing contribute to the formation of the subsequent elevated stratopause