Intercomparison of phenological transition dates derived from the PhenoCam Dataset V1.0 and MODIS satellite remote sensing

Phenology is a valuable diagnostic of ecosystem health, and has applications to environmental monitoring and management. Here, we conduct an intercomparison analysis using phenological transition dates derived from near-surface PhenoCam imagery and MODIS satellite remote sensing. We used approximately 600 site-years of data, from 128 camera sites covering a wide range of vegetation types and climate zones. During both “greenness rising” and “greenness falling” transition phases, we found generally good agreement between PhenoCam and MODIS transition dates for agricultural, deciduous forest, and grassland sites, provided that the vegetation in the camera field of view was representative of the broader landscape. The correlation between PhenoCam and MODIS transition dates was poor for evergreen forest sites. We discuss potential reasons (including sub-pixel spatial heterogeneity, flexibility of the transition date extraction method, vegetation index sensitivity in evergreen systems, and PhenoCam geolocation uncertainty) for varying agreement between time series of vegetation indices derived from PhenoCam and MODIS imagery. This analysis increases our confidence in the ability of satellite remote sensing to accurately characterize seasonal dynamics in a range of ecosystems, and provides a basis for interpreting those dynamics in the context of tangible phenological changes occurring on the ground

Evaluating multiple causes of persistent low microwave backscatter from Amazon forests after the 2005 drought

Amazonia has experienced large-scale regional droughts that affect forest productivity and biomass stocks. Space-borne remote sensing provides basin-wide data on impacts of meteorological anomalies, an important complement to relatively limited ground observations across the Amazon’s vast and remote humid tropical forests. Morning overpass QuikScat Ku-band microwave backscatter from the forest canopy was anomalously low during the 2005 drought, relative to the full instrument record of 1999–2009, and low morning backscatter persisted for 2006–2009, after which the instrument failed. The persistent low backscatter has been suggested to be indicative of increased forest vulnerability to future drought. To better ascribe the cause of the low post-drought backscatter, we analyzed multiyear, gridded remote sensing data sets of precipitation, land surface temperature, forest cover and forest cover loss, and microwave backscatter over the 2005 drought region in the southwestern Amazon Basin (4°-12°S, 66°-76°W) and in adjacent 8°x10° regions to the north and east. We found moderate to weak correlations with the spatial distribution of persistent low backscatter for variables related to three groups of forest impacts: the 2005 drought itself, loss of forest cover, and warmer and drier dry seasons in the post-drought vs. the pre-drought years. However, these variables explained only about one quarter of the variability in depressed backscatter across the southwestern drought region. Our findings indicate that drought impact is a complex phenomenon and that better understanding can only come from more extensive ground data and/or analysis of frequent, spatially-comprehensive, high-resolution data or imagery before and after droughts

A Plan for Research on Floods and Their Mitigation in the United States

published or submitted for publicationis peer reviewedOpe

Connecting PhenoCam Sites with the ORNL DAAC MODIS Global Subsetting and Visualization Tool

The PhenoCam website (http://phenocam.unh.edu/) is tasked with acquiring, processing, and archiving web imagery from inexpensive webcams to be used for scientific studies of phenological processes. PhenoCam is currently archiving imagery from about 200 cameras mounted on towers, buildings, and other permanent structures, with a view across the top of the vegetation canopy. From this image data we extract time series of gcc (green chromatic coordinate) values, which contain a seasonal phenological signal for the local canopy. One goal of the PhenoCam project is to compare this no-altitude remote sensing data with space-borne remote sensing data. This is a common task faced by many low- and no-altitude observatories. Here we report on linking PhenoCam time series camera data (gcc time series) with MODIS Vegetation Index (EVI/NDVI) time series data using the Oak Ridge National Lab Distributed Active Archive Center (ORNL DAAC) MODIS Global Subsetting and Visualization Tool and the associated web services. By using a combination of ORNL DAAC web services, and by automated submission of processing requests, we provide easy access to comparable time-series from the two data sources. This should facilitate the development of models to extract transition dates from the time series data and the comparison of those dates between the two data sources

Considering planned change anew: stretching large group interventions strategically, emotionally and meaningfully

Large Group Interventions, methods for involving “the whole system” in a change process, are important contemporary planned organizational change approaches. They are well known to practitioners but unfamiliar to many organizational researchers, despite the fact that these interventions address crucial issues about which many organizational researchers are concerned. On the other hand, these interventions do not appear to be informed by contemporary developments in organizational theorizing. This disconnect on both sides is problematic. We describe such interventions and their importance; illustrate them with extended descriptions of particular Future Search and Whole‐Scale™ change interventions; summarize research on strategy, emotion, and sensemaking that may inform them; and suggest questions about the interventions that may stimulate research and reflection on practice. We also discuss conditions that may foster effective engagement between Large Group Interventions practitioners and organizational researchers. Our approach represents a way to conduct a review that combines scholarly literature and skilled practice and to initiate a dialog between them

Beyond UNCED: an introduction

It is doubtful whether the United Nations Conference on Environment and Development (UNCED) and its output were appropriate for averting global environmental and developmental catastrophe. At the most fundamental level, the causes of environmental degradation have not been addressed, and without this, efforts to tackle the crisis are bound to fail. The crisis is rooted in the process of globalisation under way. Powerful entrenched interests impede progress in understanding the crisis and in addressing it. They marginalise rival interpretations of its origins and thereby block the discovery of possible ways forward. The intellectual debate inside and outside UNCED has been dominated by these entrenched interests. This monopoly on respectable knowledge determines the allocation of responsibility and consequent remedial action. The result is that the crisis is to be tackled by a continuation of the very policies that have largely caused it in the first place. The interstate system is incapable of dealing with the crisis. The state itself is suffering from a crisis of legitimacy and a crisis of capacity. In some ways it is too small for dealing with the crisis, which has global aspects; in other ways it is too big, given the local aspects. These crises pose opportunities for, as well as obstacles to, the emergence from the outmoded structure of the interstate system of a global society based on fundamental human rights. The crisis of the state is stimulating discussion about political identity, human rights, democracy and accountability. It opens up space for real discussion of a new world order and the role of democratic participation below and between states, and on which the whole sustainability process ultimately depends