21 research outputs found
Terrestrial mammals of a sheep-grazing property on Bruny Island, Tasmania
Land-based mammals were surveyed in a mosaic of dry sclerophyll forests and pasture on a sheep-grazing property on Bruny Island, Tasmania, using a range of methods in August 2010. 'This is the first mammal survey of a sheep-grazing property in Tasmania and the first large-scale survey of mammals on Bruny Island. Ten species were recorded comprising seven native and three introduced species. The Little Forest Bat, Vespadelus vulturnus, and the Black Rat, Rattus rattus, were recorded for the first time on Bruny Island, although both are probably long-term residents. No mammal species listed as rare or threatened under Tasmanian or Australian legislation were found on the property. Large numbers of Eastern Quolls, Dasyurus viverrinus, Brushtail Possums, Trichosurus vulpecula, Tasmanian Pademelons, Thylogale billardierii, and Bennetts Wallabies, Macropus rufogriseus, were recorded in a range of dry sclerophyll forests and in pasture. Longnosed Potoroos, Potorous tridactylus, were recorded widely on the property in native vegetation with relatively thick ground cover. Eastern Quoll capture rates were highest in pasture areas and in Eucalyptus ovata forest. Brushtail Possums, Long-nosed Potoroos, Tasmanian Pademelons and Bennetts Wallabies were virtually unrecorded from E. tenuiramis forest and woodlands. Given the level of survey effort and their potential to occur on the property it was remarkable that no Tasmanian Bettong, Bettongia gaimardi, Eastern Barred Bandicoot, Perameles gunnii, Southern Brown Bandicoot, lsoodon obesulus, or introduced House Mouse, Mus musculus, were recorded. We found that camera trapping was more cost-efficient than cage trapping for detecting the presence of mammals on "Murrayfield". Recommendations for ongoing management and monitoring of mammals are provided
Validation of the Aura Microwave Limb Sounder HNOmeasurements
We assess the quality of the version 2.2 (v2.2) HNO3 measurements from the Microwave Limb Sounder (MLS) on the Earth Observing System Aura satellite. The MLS HNO3 product has been greatly improved over that in the previous version (v1.5), with smoother profiles, much more realistic behavior at the lowest retrieval levels, and correction of a high bias caused by an error in one of the spectroscopy files used in v1.5 processing. The v2.2 HNO3 data are scientifically useful over the range 215 to 3.2 hPa, with single-profile precision of âŒ0.7 ppbv throughout. Vertical resolution is 3â4 km in the upper troposphere and lower stratosphere, degrading to âŒ5 km in the middle and upper stratosphere. The impact of various sources of systematic uncertainty has been quantified through a comprehensive set of retrieval simulations. In aggregate, systematic uncertainties are estimated to induce in the v2.2 HNO3 measurements biases that vary with altitude between ±0.5 and ±2 ppbv and multiplicative errors of ±5â15% throughout the stratosphere, rising to âŒÂ±30% at 215 hPa. Consistent with this uncertainty analysis, comparisons with correlative data sets show that relative to HNO3 measurements from ground-based, balloon-borne, and satellite instruments operating in both the infrared and microwave regions of the spectrum, MLS v2.2 HNO3 mixing ratios are uniformly low by 10â30% throughout most of the stratosphere. Comparisons with in situ measurements made from the DC-8 and WB-57 aircraft in the upper troposphere and lowermost stratosphere indicate that the MLS HNO3 values are low in this region as well, but are useful for scientific studies (with appropriate averaging)
Validation of Aura Microwave Limb Sounder O-3 and CO observations in the upper troposphere and lower stratosphere
International audienceGlobal satellite observations of ozone and carbon monoxide from the Microwave Limb Sounder (MLS) on the EOS Aura spacecraft are discussed with emphasis on those observations in the 215â100 hPa region (the upper troposphere and lower stratosphere). The precision, resolution and accuracy of the data produced by the MLS âversion 2.2â processing algorithms are discussed and quantified. O3 accuracy is estimated at ~40 ppbv +5% (~20 ppbv +20% at 215 hPa) while the CO accuracy is estimated at ~30 ppbv +30% for pressures of 147 hPa and less. Comparisons with expectations and other observations show good agreements for the O3 product, generally consistent with the systematic errors quoted above. In the case of CO, a persistent factor of ~2 high bias is seen at 215 hPa. However, the morphology is shown to be realistic, consistent with raw MLS radiance data, and useful for scientific study. The MLS CO data at higher altitudes are shown to be consistent with other observations
Validation of the Aura Microwave Limb Sounder HNO3 Measurements
We assess the quality of the version 2.2 (v2.2) HNO3 measurements from the
Microwave Limb Sounder (MLS) on the Earth Observing System Aura satellite. The MLS
HNO3 product has been greatly improved over that in the previous version (v1.5), with
smoother profiles, much more realistic behavior at the lowest retrieval levels, and
correction of a high bias caused by an error in one of the spectroscopy files used in v1.5
processing. The v2.2 HNO3 data are scientifically useful over the range 215 to 3.2 hPa,
with single-profile precision of 0.7 ppbv throughout. Vertical resolution is 3â4 km in the
upper troposphere and lower stratosphere, degrading to 5 km in the middle and
upper stratosphere. The impact of various sources of systematic uncertainty has been
quantified through a comprehensive set of retrieval simulations. In aggregate, systematic
uncertainties are estimated to induce in the v2.2 HNO3 measurements biases that vary with
altitude between ±0.5 and ±2 ppbv and multiplicative errors of ±5â15% throughout the
stratosphere, rising to ±30% at 215 hPa. Consistent with this uncertainty analysis,
comparisons with correlative data sets show that relative to HNO3 measurements from
ground-based, balloon-borne, and satellite instruments operating in both the infrared
and microwave regions of the spectrum, MLS v2.2 HNO3 mixing ratios are uniformly low
by 10â30% throughout most of the stratosphere. Comparisons with in situ measurements
made from the DC-8 and WB-57 aircraft in the upper troposphere and lowermost
stratosphere indicate that the MLS HNO3 values are low in this region as well, but are
useful for scientific studies (with appropriate averaging).PublishedD24S401.7. Osservazioni di alta e media atmosferaJCR Journalreserve
Validation of the Aura Microwave Limb Sounder Temperature and Geopotential Height Measurements
Global satellite observations of temperature and geopotential height (GPH) from the Microwave Limb Sounder (MLS) on the EOS Aura spacecraft are discussed. The precision, resolution, and accuracy of the data produced by the MLS version 2.2 processing algorithms are quantified, and recommendations for data screening are made. Temperature precision is 1 K or better from 316 hPa to 3.16 hPa, degrading to âŒ3 K at 0.001 hPa. The vertical resolution is 3 km at 31.6 hPa, degrading to 6 km at 316 hPa and to âŒ13 km at 0.001 hPa. Comparisons with analyses (Goddard Earth Observing System version 5.0.1 (GEOS-5), European Centre for Medium-range Weather Forecasts (ECMWF), Met Office (MetO)) and other observations (CHAllenging Minisatellite Payload (CHAMP), Atmospheric Infrared Sounder/Advanced Microwave Sounder Unit (AIRS/AMSU), Sounding of the Atmosphere using Broadband Radiometry (SABER), Halogen Occultation Experiment (HALOE), Atmospheric Chemistry Experiment (ACE), radiosondes) indicate that MLS temperature has persistent, pressure-dependent biases which are between â2.5 K and +1 K between 316 hPa and 10 hPa. The 100-hPa MLS v2.2 GPH surface has a bias of âŒ150 m relative to the GEOS-5 values. These biases are compared to modeled systematic uncertainties. GPH biases relative to correlative measurements generally increase with height owing to an overall cold bias in MLS temperature relative to correlative temperature measurements in the upper stratosphere and mesosphere
Memristive Behavior in Electrohydrodynamic Atomized Layers of Poly[2-methoxy-5-(2'-ethylhexyloxy)â( p
Anomalous temperature dependence of the current in a metal-oxide-polymer resistive switching diode
Metal-oxide polymer diodes exhibit non-volatile resistive switching. The currentâvoltage characteristics have been studied as a function of temperature. The low-conductance state follows a thermally activated behaviour. The high-conductance state shows a multistep-like behaviour and below 300 K an enormous positive temperature coefficient. This anomalous behaviour contradicts the widely held view that switching is due to filaments that are formed reversibly by the diffusion of metal atoms. Instead, these findings together with small-signal impedance measurements indicate that creation and annihilation of filaments is controlled by filling of shallow traps localized in the oxide or at the oxide/polymer interfac
Validation of the Aura Microwave Limb Sounder HNO3 Measurements
We assess the quality of the version 2.2 (v2.2) HNO3 measurements from the
Microwave Limb Sounder (MLS) on the Earth Observing System Aura satellite. The MLS
HNO3 product has been greatly improved over that in the previous version (v1.5), with
smoother profiles, much more realistic behavior at the lowest retrieval levels, and
correction of a high bias caused by an error in one of the spectroscopy files used in v1.5
processing. The v2.2 HNO3 data are scientifically useful over the range 215 to 3.2 hPa,
with single-profile precision of 0.7 ppbv throughout. Vertical resolution is 3â4 km in the
upper troposphere and lower stratosphere, degrading to 5 km in the middle and
upper stratosphere. The impact of various sources of systematic uncertainty has been
quantified through a comprehensive set of retrieval simulations. In aggregate, systematic
uncertainties are estimated to induce in the v2.2 HNO3 measurements biases that vary with
altitude between ±0.5 and ±2 ppbv and multiplicative errors of ±5â15% throughout the
stratosphere, rising to ±30% at 215 hPa. Consistent with this uncertainty analysis,
comparisons with correlative data sets show that relative to HNO3 measurements from
ground-based, balloon-borne, and satellite instruments operating in both the infrared
and microwave regions of the spectrum, MLS v2.2 HNO3 mixing ratios are uniformly low
by 10â30% throughout most of the stratosphere. Comparisons with in situ measurements
made from the DC-8 and WB-57 aircraft in the upper troposphere and lowermost
stratosphere indicate that the MLS HNO3 values are low in this region as well, but are
useful for scientific studies (with appropriate averaging)
Validation of Aura Microwave Limb Sounder Ozone by Ozonesonde and Lidar Measurements
We present validation studies of MLS version 2.2 upper tropospheric and stratospheric ozone profiles using ozonesonde and lidar data as well as climatological data. Ozone measurements from over 60 ozonesonde stations worldwide and three lidar stations are compared with coincident MLS data. The MLS ozone stratospheric data between 150 and 3 hPa agree well with ozonesonde measurements, within 8% for the global average. MLS values at 215 hPa are biased high compared to ozonesondes by approximately 20% at middle to high latitude, although there is a lot of variability in this altitude region