Joint Global Change Research Institute

About: Joint Global Change Research Institute is a facility organization based out in Riverdale Park, Maryland, United States. It is known for research contribution in the topics: Greenhouse gas & Climate change. The organization has 197 authors who have published 934 publications receiving 62390 citations.

Global health and natural disaster alerts: preparing mobile phones to endure the unthinkable

Abstract: Despite the increasingly positive role of portable communication technologies for socioeconomic development and their growing use in global health and other emergency contexts, several challenges still hinder exploring the full potential of mobile phones as effective mitigation tools in natural disasters, public health emergencies and in the aftermath of extreme disruptive events. Mobile devices are designed and advertised to withstand predominantly the demands of normal daily situations, being fraught with fragilities that limit their utility for effective communication and coordination of help in emergency situations. We discuss ways to overcome some of these limitations in the future by the incorporation of features to increase their resilience and effectiveness as aid tools at relatively low cost. Improvements in autonomous energy generation and use, based on existing and rapidly emerging technologies, as well as further improvements in physical durability and off-line operability are encouraged. We also identify the possibility to combine capabilities from other devices, such as space-based telecommunication systems and traditional two-way radios, to enhance the utility of mobile devices for these applications. The solutions we propose can help millions of citizens around the world to manage the risks and impacts of natural and health-related hazards. They should also promote further resilience to avoiding and recovering from such events, especially in vulnerable regions with limited infrastructure.

Soil Respiration Response to Simulated Precipitation Change Depends on Ecosystem Type and Study Duration

Abstract: Soil respiration—the flow of biologically-generated CO2 from the soil surface to the atmosphere—is a major component of global carbon cycling, but the long-term response of this flux to altered precipitation regimes remains uncertain, due to different responses of soil respiration in distinct ecosystems with varying degrees of water limitation. We conducted a meta-analysis to determine the role of soil characteristics (organic carbon stock and clay content), study duration, and ecosystem type (e.g., forest, grassland, etc) in modifying the response of soil respiration to precipitation change. In general, decreased precipitation (N = 128 effect size pairs) decreased soil respiration rates. In contrast, increased precipitation (N = 141) had a more variable and on-average weak positive effect on this flux; significantly increasing soil respiration only in desert ecosystems. The long-term response of ecosystems varied, with those that are less constrained by water-availability (e.g., forests) showing acclimation over time to altered precipitation. Soil organic carbon stock strongly modified the response of soil respiration to decreased precipitation (p < 0.0001), but only weakly modified the response to increased precipitation (p < 0.01). Our results suggest that ecosystems with limited soil water-holding capacity and strong inherent water-limitation will show long-term dynamic change in soil respiration regardless of the direction of precipitation change.

Hydrogeochemical characteristic evaluation and irrigation suitability assessment of shallow groundwater in Dangshan County, China

Abstract: The current study aims to identify the hydrogeochemical characteristics, formation mechanism and evolution law of shallow groundwater in Dangshan, China, and to evaluate the suitability of the groundwater for irrigation. In this study, ninety-six samples were taken to investigate the hydrogeochemical characteristics of shallow groundwater in Dangshan County. The geographic information system (GIS) method was used to analyse the spatial distribution characteristics of total dissolved solids (TDS). Gibbs diagram, Binary relation analysis and reverse geochemical reaction simulation method were utilised to reveal the main formation mechanism of relatively high TDS in this region. The results show that water-rock interaction and evapotranspiration are the main mechanisms for controlling the chemical evolution of shallow groundwater in wet and dry seasons in the study area, respectively. The main waterrock interactions in the study area include dissolution of halite and dolomite, the precipitation of gypsum, as well as cation exchange and adsorption. Suitability of shallow groundwater quality for irrigation use was evaluated according to the sodium adsorption ratio (SAR) and the electrical conductivity (EC) with a United States Salinity Laboratory (USSL) diagram. Meanwhile, GIS technology was used to demonstrate the spatial distribution of irrigation suitability variations. Based on the spatial interpolation result on the USSL salinity diagram classification, the shallow groundwater in 89% of the study area is suitable for irrigation, while 11% of the area is unsuitable for irrigation.

Cleaning cars, grid and air

Abstract: Integrated urban energy–economy–climate scenarios can be built upon bottom-up models that simulate realistic system interactions. One such model for New York shows how electrification of the vehicle fleet and grid decarbonization can reduce carbon emissions and pollution.