Retrievals of Antarctic aerosol characteristics using a Sun-sky radiometer during the 2001-2002 austral summer campaign

In order to characterize the Antarctic aerosol and to analyze the effect of katabatic winds on the properties of suspended particles, measurements of solar direct and diffuse irradiance were carried out at the Italian Terra Nova Bay station in Antarctica, during the 2001-2002 austral summer campaign. Measurements were performed by the ground-based PREDE sky radiometer and processed by using the Skyrad inversion code. Aerosol optical thickness at 500 nm was found to vary between 0.01 and 0.02. The volume size distribution curves showed bimodal features with the two modes located within 0.1-0.3 μm and 5-7 μm radius intervals, respectively. The real part of the refractive index characterizing the Antarctic aerosol was found to have a mean value of 1.40. During the katabatic event the analysis indicated that the advection of larger and drier fresh particles, together with the removal of marine suspended particles, caused the decrease in aerosol optical thickness

Energetic particle influence on the Earth's atmosphere

This manuscript gives an up-to-date and comprehensive overview of the effects of energetic particle precipitation (EPP) onto the whole atmosphere, from the lower thermosphere/mesosphere through the stratosphere and troposphere, to the surface. The paper summarizes the different sources and energies of particles, principally galactic cosmic rays (GCRs), solar energetic particles (SEPs) and energetic electron precipitation (EEP). All the proposed mechanisms by which EPP can affect the atmosphere are discussed, including chemical changes in the upper atmosphere and lower thermosphere, chemistry-dynamics feedbacks, the global electric circuit and cloud formation. The role of energetic particles in Earth’s atmosphere is a multi-disciplinary problem that requires expertise from a range of scientific backgrounds. To assist with this synergy, summary tables are provided, which are intended to evaluate the level of current knowledge of the effects of energetic particles on processes in the entire atmosphere

Bright polar mesospheric clouds formed by main engine exhaust from the space shuttle's final launch

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94747/1/jgrd18009.pd

Technology and Communications Coursework: Facilitating the Progression of Students with Learning Disabilities through High School Science and Math Coursework

Students identified with learning disabilities experience markedly lower levels of science and mathematics achievement than students who are not identified with a learning disability. Seemingly compounding their disadvantage, students with learning disabilities also complete more credits in non-core coursework—traditionally considered nonacademic coursework—than students who are not identified with a learning disability. The Education Longitudinal Study of 2002, a large national dataset with both regular and special education high school students, is utilized to determine whether credit accumulation in certain types of non-core coursework, such as technology and communications courses, is associated with improved science and math course taking outcomes for students with learning disabilities. Results show that credit accumulation in technology and communications coursework uniquely benefits the science course taking, and comparably benefits the math course taking, of students identified with learning disabilities in contrast to students who are not identified with learning disabilities