Why the earth observing system matters to all of us

Whether the collective impacts of humans on the Earth are benign, or on a trajectory to future disaster is an ethical question we must now confront. However, studying the entire Spaceship Earth as a functioning Earth System had never been tried before, until now

The 5 Stages of Climate Grief

The global warming topic seems to now be saturating the media. Newspapers, television, weekly magazines and endless Internet sites all have summaries of the science, and wide ranging discussions of what society should do next. The global warming trends and projections are sobering, even frightening, eliciting puzzling responses from the public

A Blueprint for Improved Global Change Monitoring of the Terrestrial Biosphere

The Kyoto Earth Summit recently ended, amid substantial disagreement over current and future global change, and their significance to humankind. The core of the problem is that many global leaders are unconvinced that significant global change is now occurring. Further, there is insufficient confidence in the accuracy of global-scale computer models that project future changes to initiate the political and economic re-directions that would be required to alleviate the problem. As was first said years ago, we are conducting the first global-scale biogeochemistry experiment, the outcome of which is not known, and which could severely impact the habitability of the planet. Conversely, any meaningful reduction in fossil fuel consumption will require the redirection of trillions of dollars of the world economy. The decision to embark on a serious redirection of world energy consumption is, along with population control, possibly the most fundamental global policy of the next century

MODIS Vegetation Workshop Report

The Land Science Team for the NASA Earth Observing System Moderate Resolution Imaging Spectroradiometer (MODIS) sensor [modis-land.gsfc.nasa.gov/] held a special workshop to present analysis of the first year (2001) of MODIS satellite data

Testing Forest-BGC Ecosystem Process Simulations Across a Climatic Gradient in Oregon

Field measurements from the Oregon Transect Ecological Research project (OTTER) were used to validate selected process simulations in the FOREST—BGC ecosystem model. Certain hydrologic, carbon, and nitrogen cycle process simulations were tested in this validation, either comparatively across sites, or seasonally at single sites. The range of simulated ecosystem—process rates across the OTTER sites was large; annual evapotranspiration (ET) ranged from 15 to 82 cm, net photosynthesis (as carbon) from 2.2 to 22.8 Mg/ha, and decomposition (as carbon) from 1.0 to 7.2 Mg°ha—1°yr—1. High correlations between predicted and measured data were found for: aboveground net primary production, R2 = 0.82; 100—yr stem biomass, R2 = 0.79; and average leaf nitrogen concentration, R2 = 0.88. However, correlations for pre—dawn leaf water potential and equilibrium leaf area index (LAI) were much lower, because successful simulation of these variables requires accurate data for soil water—holding capacity. Defining the water—holding capacity of the rooting zone and the maximum surface conductance for photosynthesis and transpiration rates proved to be critical system variables that defied routine field measurement. Although many other processes are simulated in FOREST—BGC, no other processes had repeated field data sets for validations. Problems in parameterizing the model from disparate data sets are also evaluated, with suggestions for using ecosystem modeling in future integrated research programs

Environmental and physiological control of water flux through Pinus contorta

This study reports measurements of leaf conductance, leaf water potential, temperature, humidity, and radiation collected on a stand of Pinuscontorta Dougl. ex Loud, lodgepole pine throughout a growing season at the Fraser Experimental Forest in central Colorado, U.S.A. The daily range of leaf conductances decreased 10-fold from June through August. A high correlation (R2 = 0.75) was found between predawn leaf water potential and morning maximum leaf conductance. Low atmospheric humidity significantly decreased midday leaf conductance. A comparison with humidity responses published for other conifers showed good agreement with this study. Seasonal change in total soil–plant resistance to water flux was nonlinearly correlated (R2 = 0.99) with change in predawn leaf water potential, an indirect measure of soil water potential

A regional look at HANPP: human consumption is increasing, NPP is not

Abdi et al (2014 Environ. Res. Lett. 9 094003), have adapted the concept of comparing supply and demand of annual plant production known as human appropriation of net primary production (HANPP) to a region of the Sahel with rapid population growth. They found that HANPP more than doubled over the study period of 2000–2010, from 19% to 41%, suggesting increasing vulnerability of these populations to food insecurity

A bottom-up evolution of terrestrial ecosystem modeling theory, and ideas toward global vegetation modeling

A primary purpose of this review is to convey lessons learned in the development of a forest ecosystem modeling approach, from it origins in 1973 as a single-tree water balance model to the current regional applications. The second intent is to use this accumulated experience to offer ideas of how terrestrial ecosystem modeling can be taken to the global scale: earth systems modeling. A logic is suggested where mechanistic ecosystem models are not themselves operated globally, but rather are used to 'calibrate' much simplified models, primarily driven by remote sensing, that could be implemented in a semiautomated way globally, and in principle could interface with atmospheric general circulation models (GCM's)