River networks as ecological corridors for species, populations, and pathogens

Will future large-scale water resources plans make compelling arguments for including the reduction of the loss of biodiversity across scales in fluvial landscapea? Is the structure of river networks a template for large-scale spread of waterborne disease infections? Are we capable to provide solid economic arguments for preventing water development schemes in the light of the social and economic cost of predicted increased burden of disease they would bring? Do biological invasions, including...

The Physics of High CAPE

Severe convective storms are a significant source of weather-related losses and injury, worldwide. Yet very little is known about what sets their climatology in the current climate, and why climate models generally indicate increased severe storm activity as the climate warms. In this talk, I will focus on one of the main ingredients in severe convective storms: Convective Available Potential Energy (CAPE). The global climatology of CAPE differs significantly from that of deep convection in general; for example, high CAPE values are quite rare over...

The Plants and Climate Reading Group meets biweekly to discuss papers spanning a range of topics, from plant physiology to land-...

Do stomata respond to variations in atmospheric humidity?

A growing literature argues that ecosystem-scale evapotranspiration is more sensitive to drying of the atmosphere because of stomatal regulation by plants than to reductions in surface soil moisture. Past studies analyzed observations, for which it is difficult to conclusively control for potential relations between plant physiology, measurable state variables like vapor pressure deficit (VPD) or soil moisture, and the ecosystem-scale water flux. Here, we analyze natural mechanism-denial experiments at non-vegetated...

From Early Earth to Acid Rain and Agriculture: A Broad Look at the Changing Global Sulfur Cycle

Sulfur (S) is a key component of life and an element that has been dramatically changed by human industrial activities, including mining and fossil fuel combustion. Today, the nature of how humans alter the global S cycle is changing. As atmospheric S deposition has declined in response to air quality regulations in the United States and Europe, there has been an increase in S fertilizer applications reported in many large-scale regional crop systems. In addition, intensification...

‘Picking your path’ towards accessible and inclusive geoscience field education

Fieldwork is a critical aspect of geoscience education and there is now a substantive body of research-informed evidence to support its continued inclusion in the undergraduate geoscience curriculum. However, while the value of fieldwork for understanding the Earth and Earth processes is well established, fieldwork as an activity is not inclusive or accessible for all students. This is particularly true for students with disabilities who can encounter multiple barriers to participating in...

Forest Recovery from Hurricane Disturbances

Hurricanes are a major disturbance to tropical forests. We used census observations at Bisley Experimental Watersheds (BEW) in Puerto Rico to study the mortality after hurricane Hugo in 1989 and after hurricane Maria in 2017 and the subsequent recovery of the forest after hurricane Hugo between 1989 and 2014 (the last census before hurricane Maria). We found that hurricane-induced mortality varied with species/plant functional types (PFTs) and stem sizes. Specifically, palms had the lowest mortality, followed by mid and late...

Surface Evaporation and Rainfall Partitioning in Arid Lands - Local and global perspectives

The presentation will explore two interconnected vignettes related to surface evaporation. In the first part we will review basic aspects of surface evaporation and discuss how soil type modulates evaporation dynamics via surface resistance and internal drainage that shelter infiltrated rainwater from evaporation losses (but not from plant water uptake). These basic elements offer a simple pathway for estimation of surface evaporation losses locally and globally. In the second part,...