Dynamic evaluation of modeled ozone concentrations in Germany with four chemistry transport models.

Simulating the ozone variability at regional scales using chemistry transport models (CTMs) remains a challenge. We designed a multi-model intercomparison to evaluate, for the first time, four regional CTMs on a national scale for Germany. Simulations were conducted with LOTOS-EUROS, REM-CALGRID, COSMO-MUSCAT and WRF-Chem for January 1 to December 31, 2019, using prescribed emission information.

The Global Atmosphere-aerosol Model ICON-A-HAM2.3-Initial Model Evaluation and Effects of Radiation Balance Tuning on Aerosol Optical Thickness.

The Hamburg Aerosol Module version 2.3 (HAM2.3) from the ECHAM6.

Particle-Phase Photoreactions of HULIS and TMIs Establish a Strong Source of HO and Particulate Sulfate in the Winter North China Plain.

During haze periods in the North China Plain, extremely high NO concentrations have been observed, commonly exceeding 1 ppbv, preventing the classical gas-phase HO formation through HO recombination. Surprisingly, HO mixing ratios of about 1 ppbv were observed repeatedly in winter 2017. Combined field observations and chamber experiments reveal a photochemical in-particle formation of HO, driven by transition metal ions (TMIs) and humic-like substances (HULIS).

Estimating densities of larval Salmonflies (Pteronarcys californica) through multiple pass removal of post-emergent exuvia in Colorado rivers.

Traditional methods of collecting, sorting, and identifying benthic macroinvertebrate samples are useful for stream biomonitoring and ecological studies, however, these methods are time consuming, expensive, and require taxonomic expertise. Estimating larval densities through collection of post-emergent exuvia can be a practical and time efficient alternative. We evaluated the use of multiple pass depletion techniques of the post-emergent exuvia of Pteronarcys californica to estimate larval densities at ten sites in three Colorado rivers.

Discovery of new populations and DNA barcoding of the Arapahoe snowfly Arsapnia arapahoe (Plecoptera: Capniidae).

The Arapahoe Snowfly, Arsapnia arapahoe (Nelson & Kondratieff)was recently discovered in six different first-order streams outside of the Cache la Poudre River Basin where it was previously considered endemic. Specimens of A. arapahoe were always collected in much lower relative abundance, 1.