Roads have been a part of human landscapes for more than 40 centuries. During the 20th century, technological advances have increased our ability to construct new roads at unprecedented rates and into steeper terrain. In the last half of that century, an extensive network of roads has been constructed in forests and other wildlands to facilitate use and management of natural resources. They are...

The “perfect storm” metaphor describes the improbable coincidence of several different forces or factors to produce an unusual outcome. The perfect landscape is conceptualized as a result of the combined, interacting effects of multiple environmental controls and forcings to produce an outcome that is highly improbable, in the sense of the likelihood of duplication at any other place or time. G...

The increasing frequency and/or severity of extreme climate events are becoming increasingly apparent over multidecadal timescales at the global scale, albeit with relatively low scientific confidence. At the regional scale, scientific confidence in the future trends of extreme event likelihood is stronger, although the trends are spatially variable. Confidence in these extreme climate risks is...

Introduction: Since the Viking and Mariner 9 missions of nearly a quarter of a century ago provided global coverage of the Martian landscape at resolutions of 100-150m/pixel, a plethora of science related information pertaining to Mars and its landscape have become available to the scientific community. This information includes comprehensive global topography (MOLA), both low (Viking) and high...

Climbing dunes are typical aeolian landforms. The study of their formation and development mechanisms is necessary for the prevention control dune migration. gradient shape important geomorphic factors affecting climbing dunes, but influencing mechanism not clear at present. In this work, wind speed sand deposition on a sloping surface were monitored constant 8 m s−1 in wind-tunnel experiments,...

Acknowledgments T he Nearshore Science Team (NST) of the Puget Sound Nearshore Project recognized in early discussions the need for a geomorphic framework to guide shoreline restoration planning. These individuals clarified the rationale and the purpose for this document and provided valuable comments on early drafts of the report. This project also benefitted greatly from the input of Washingt...

[1] Many Hesperian outflow channels head at elevations compatible with aquifer recharge beneath the Martian south polar cap, and such channels are widely interpreted as the products of this recharge. Some outflow channels head at greater elevations that are inconsistent with southern recharge, including three systems located in Aurorae Planum and eastern Ophir Planum. These three systems have p...