Jonathan M. Gilligan

Household actions can provide a behavioral wedge to rapidly reduce US carbon emissions

Most climate change policy attention has been addressed to long-term options, such as inducing new, low-carbon energy technologies and creating cap-and-trade regimes for emissions. We use a behavioral approach to examine the reasonably achievable potential for near-term reductions by altered adoption and use of available technologies in US homes and nonbusiness travel. We estimate the plasticity of 17 household action types in 5 behaviorally distinct categories by use of data on the most effective documented interventions that do not involve new regulatory measures. These interventions vary by type of action and typically combine several policy tools and strong social marketing. National implementation could save an estimated 123 million metric tons of carbon per year in year 10, which is 20% of household direct emissions or 7.4% of US national emissions, with little or no reduction in household well-being. The potential of household action deserves increased policy attention. Future analyses of this potential should incorporate behavioral as well as economic and engineering elements.

Evaluation of source gas lifetimes from stratospheric observations

Simultaneous in situ measurements of the long-lived trace species N2O, CH4, 12, CFC-113, CFC-11, CCl4, CH3CCl3, H-1211, and SF6 were made in the lower stratosphere and upper troposphere on board the NASA ER-2 high-altitude aircraft during the 1994 campaign Airborne Southern Hemisphere Ozone Experiment/ Measurements for Assessing the Effects of Stratospheric Aircraft. The observed extratropical tracer abundances exhibit compact mutual correlations that show little interhemispheric difference or seasonal variability except at higher altitudes in southern hemisphere spring. The environmental impact of the measured source gases depends, among other factors, on the rate at which they release ozone-depleting chemicals in the stratosphere, that is, on their stratospheric lifetimes. We calculate the mean age of the air from the SF6 measurements and show how stratospheric lifetimes of the other species may be derived semiempirically from their observed gradients with respect to mean age at the extratropical tropopause. We also derive independent stratospheric lifetimes using the CFC-11 lifetime and the slopes of the tracers correlations with CFC-11. In both cases, we correct for the influence of tropospheric growth on stratospheric tracer gradients using the observed mean age of the air, time series of observed tropospheric abundances, and model-derived estimates of the width of the stratospheric age spectrum. Lifetime results from the two methods are consistent with each other. Our best estimates for stratospheric lifetimes are 122±24 years for N2O, 93±18 years for CH4, 87±17 years for CFC-12, 100±32 years for CFC-113, 32±6 years for CCl4, 34±7 years for CH3CCl3, and 24±6 years for H-1211. Most of these estimates are significantly smaller than currently recommended lifetimes, which are based largely on photochemical model calculations. Because the derived stratospheric lifetimes are identical to atmospheric lifetimes for most of the species considered, the shorter lifetimes would imply a faster recovery of the ozone layer following the phaseout of industrial halocarbons than currently predicted.

Quantifying Transport Between the Tropical and Mid-Latitude Lower Stratosphere

Airborne in situ observations of molecules with a wide range of lifetimes (methane, nitrous oxide, reactive nitrogen, ozone, chlorinated halocarbons, and halon-1211), used in a tropical tracer model, show that mid-latitude air is entrained into the tropical lower stratosphere within about 13.5 months; transport is faster in the reverse direction. Because exchange with the tropics is slower than global photochemical models generally assume, ozone at mid-latitudes appears to be more sensitive to elevated levels of industrial chlorine than is currently predicted. Nevertheless, about 45 percent of air in the tropical ascent region at 21 kilometers is of mid-latitude origin, implying that emissions from supersonic aircraft could reach the middle stratosphere.

Airborne gas chromatograph for in situ measurements of long-lived species in the upper troposphere and lower stratosphere

A new instrument, the Airborne Chromatograph for Atmospheric Trace Species IV (ACATS-IV), for measuring long-lived species in the upper troposphere and lower stratosphere is described. Using an advanced approach to gas chromatography and electron capture detection, the instrument can detect low levels of CFC-11 (CCl 3 F), CFC-12 (CCl 2 F 2 ), CFC-113 (CCl 2 F-CClF 2 ), methyl chloroform (CH 3 CCl 3 ), carbon tetrachloride (CCl 4 ), nitrous oxide N 2 O), sulfur hexafluoride (SF 6 ), Halon-1211 (CBrClF 2 ), hydrogen (H 2 ), and methane (CH 4 ) acquired in ambient samples every 180 or 360 s. The instrument operates fully-automated onboard the NASA ER-2 high-altitude aircraft on flights lasting up to 8 hours or more in duration. Recent measurements include 24 successful flights covering a broad latitude range (70°S-61°N) during the Airborne Southern Hemisphere Ozone Experiment/Measurements for Assessing the Effects of Stratospheric Aircraft (ASHOE/ MAESA) campaign in 1994.

Linear Trap for High-accuracy Spectroscopy of Stored Ions

Abstract In a linear r.f. Paul trap, ‘crystallized’ structures of laser-cooled 199Hg+ ions are observed. The ground-state hyperfine transition at 40·5 GHz is observed in microwave-optical double-resonance spectroscopy. Future prospects are also discussed.

Free-electron-laser near-field nanospectroscopy

First experiments at the Vanderbilt free electron lasers measured the local reflectivity of a PtSi/Si system. The reflectivity in the scanning near-field optical microscope images revealed features that were not present in the corresponding shear-force (topology) images and which were due to localized changes in the bulk properties of the sample. The size of the smallest detected features clearly demonstrated that near-field conditions were reached. The use of different photon wavelengths (0.653, 1.2, and 2.4 μm) enabled us to probe regions of different depth.

Design Principles for Carbon Emissions Reduction Programs

Thegoal,articulatedbyPresidentObamain2009,ofreducingU.S. carbon emissions 17% from the 2005 level by 2020 iseminentlyachievablewithoutnewtechnologyorappreciablesacrifice by energy users. However, achieving it will in partrequire sophisticated energy efficiency and conservationprograms.Toovercomeinstitutionalandbehavioralbarriers,these programs will need to implement six principles ofeffectivedesignderivedfrom30yearsofbehavioralandsocialscience research. We focus on the household sector, butbelieveourgeneralconclusionslikelyapplytoothersectorsas well.We recently developed an analysis for the householdsector senergy use in homes and for nonbusiness travel ofwhat we call Reasonably Achievable Emissions Reductions(RAER) (

Scanning near field infrared microscopy using chalcogenide fiber tips

Chalcogenide glass optical fibers were fabricated into functional apertured probes for near field scanning infrared microscopy. Probe fiber tips were chemically etched and aluminum coated for the purpose of simultaneously collecting near field shear force and optical signals. Surface topography and infrared optical reflectivity data were obtained using the tips in a scanning near field microscope while illuminating an integrated microcircuit with the output from a free electron laser operating at a λ of 4.7 μm. Approximately 25 nm topographical and 100 nm optical lateral resolution were observed.

Water conservation and hydrological transitions in cities in the United States

Cities across the world have had to diversify and expand their water supply systems in response to demand growth, groundwater depletion and pollution, and instability and inadequacy of regional surface freshwater sources. In the U.S., these problems plague not only the arid Western cities but increasingly also cities in the Eastern portions of the country. Although cities continue to seek out new sources of water via Promethean projects of long-distance supply systems, desalinization plants, and the recharge of aquifers with surface water, they also pursue water conservation because of its low cost and other benefits. We examine water conservation as a complex sociotechnical system comprising interactions of political, sociodemographic, economic, and hydroclimatological factors. We provide quantitative data on the factors that affect more and less advanced transitions in water conservation regimes, and we show that water stress and other hydrological data can only partially predict the transition. We also provide qualitative case studies to identify institutional and political barriers to more advanced water conservation regimes. This interdisciplinary, mixed methods approach typifies the need for knowledge that informs hydrologists about how their research may or may not be adopted by decision-makers.

Singlemode chalcogenide fiber infrared SNOM probes

We have fabricated and tested infrared scanning near-field optical microscope (IR-SNOM) probe tips made from singlemode chalcogenide fiber. The process used to create the tips was similar to conventional micropipette-puller techniques, with some modifications to allow for the lower melting temperature and tensile strength of the chalcogenide fiber. SEM micrographs, showing tips with sub-micrometer physical dimensions, demonstrate the feasibility of this process. Topographical data obtained using a shear-force near-field microscope exhibits spatial resolution in the range 80-100 nm. Optical data in the infrared (near 3.5 mu m), using the probe tips in collection mode, indicates an optical spatial resolution approximately lambda/15