Volatile organic compound (VOC) reactivity in central California is examined using a photochemical air quality model (the Community Multiscale Air Quality model; CMAQ) and ground-based measurements to evaluate the contribution of VOC to photochemical activity. We classify VOC into four categories: anthropogenic, biogenic, aldehyde, and other oxygenated VOC. Anthropogenic and biogenic VOC consis...

One of the most concerning issues to modern ecology and society is the ongoing loss of biodiversity. Ecosystems are now losing species at rates only seen in previous mass extinction events (Hails, 2008; Barnosky et al., 2011) with rates of extinction between 100 and 1000 times higher than pre-human levels (Pimm et al., 1995). This loss, in turn, is impairing the functioning of ecosystems (Worm ...

What one experiences today as atmosphere is a transient snapshot and result of its evolutionary history. Much of the development and present status was explained based both on scientific knowledge, and combined with established facts, even speculation. The planet Earth was formed around 4600 million years ago by the gravitational accretion of relatively small rocks and dust, within the solar ne...

Dangerous Anthropogenic Interference The United Nations Framework Convention on Climate Change (UNFCCC) commits signatory nations (which includes all major nations including the United States) to stabilizing greenhouse gas concentrations at levels short of DAI. To properly define DAI, one must take into account issues that are not only scientific, but, as I have argued elsewhere (2), economic, ...

[1] Elevated mercury (Hg) in marine and terrestrial ecosystems is a global health concern because of the formation of toxic methylmercury. Humans have emitted Hg to the atmosphere for millennia, and this Hg has deposited and accumulated into ecosystems globally. Here we present a global biogeochemical model with fully coupled atmospheric, terrestrial, and oceanic Hg reservoirs to better underst...

All major rivers in northwestern Germany that flow into the North Sea, including the Weser River, display rare earth element (REE) patterns with large positive gadolinium (Gd) anomalies that indicate the presence of anthropogenic Gd derived from contrast agents used in magnetic resonance imaging. This microcontaminant cannot be removed by common sewage treatment technology and enters rivers and...

Global climate change is one of the most important issues of contemporary environmental safety. A scientific consensus is forming that the emissions of greenhouse gases, including carbon dioxide, nitrous oxide and methane, from anthropogenic activities may play a key role in elevating the global temperatures. Quantifying soil greenhouse gas emissions is an essential task for understanding the a...

For the period 1996-2010, we provide the first indication of the drivers behind mangrove land cover and land use change across the (pan-)tropics using time-series Japanese Earth Resources Satellite (JERS-1) Synthetic Aperture Radar (SAR) and Advanced Land Observing Satellite (ALOS) Phased Array-type L-band SAR (PALSAR) data. Multi-temporal radar mosaics were manually interpreted for evidence of...

Natural and anthropogenic aerosols over northern India play an important role in influencing the regional radiation budget, causing climate implications to the overall hydrological cycle of South Asia. In the context of regional climate change and air quality, we discuss aerosol loading variability and trends at Kanpur AERONET station located in the central part of the Indo-Gangetic plains (IGP...