We present an observational and theoretical study of the optical emission from nonradiative shocks in three supernova remnants: the Cygnus Loop, RCW 86 and Tycho. The spectra of these shocks are dominated by collisionally excited hydrogen Balmer lines which have both a broad component caused by proton-neutral charge exchange and a narrow component caused by excitation of cold neutrals entering ...

Climate change and land-use change are projected to be the two greatest drivers of biodiversity loss over the coming century. Land-use change has resulted in extensive habitat loss for many species. Likewise, climate change has affected many species resulting in range shifts, changes in phenology, and altered interactions. We used a spatially explicit, individual-based model to explore the effe...

Spatio-temporal changes in water temperature and discharge of the Arctic rivers are important variables to be observed not only for estimating runoff contributions from snow melt, rainfall, thawing permafrost over continents but also assessing their impacts on sea-ice marine ecosystem. Nevertheless, number ground gauging stations frequency in-situ measurements has been decreasing since 20 Centu...