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- Author or Editor: E. J. Llewellyn x
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Abstract
Measurements have been made of airflow velocities and cloud liquid water contents from selected positions around the fuselage of an F-27 aircraft. The airflow measurements away from the propeller inflow region are in reasonable agreement with those calculated in Part I. The liquid water measurements were made using two CSIRO hot-wire probes, one of which could be positioned at distances of 15–60 cm from the fuselage. Results of these comparisons showed that the enhancement factors calculated in Part I appear quite reasonable and that corrections can consequently be made to allow for sampling errors caused by fuselage-related flow distortions. The comparisons also show that there are additional sampling errors as large as 10% which depend on position of the probe relative to the wings and propeller. For the F-27 these additional effects decrease substantially with increasing aircraft speed.
Abstract
Measurements have been made of airflow velocities and cloud liquid water contents from selected positions around the fuselage of an F-27 aircraft. The airflow measurements away from the propeller inflow region are in reasonable agreement with those calculated in Part I. The liquid water measurements were made using two CSIRO hot-wire probes, one of which could be positioned at distances of 15–60 cm from the fuselage. Results of these comparisons showed that the enhancement factors calculated in Part I appear quite reasonable and that corrections can consequently be made to allow for sampling errors caused by fuselage-related flow distortions. The comparisons also show that there are additional sampling errors as large as 10% which depend on position of the probe relative to the wings and propeller. For the F-27 these additional effects decrease substantially with increasing aircraft speed.
Abstract
The trend in sea surface temperature has been determined from 20 yr of Advanced Very High Resolution Radiometer Pathfinder data (version 5). The data span the period from January 1985 to December 2004, inclusive. The linear trends were calculated to be 0.18° ± 0.04° and 0.17° ± 0.05°C decade−1 from daytime and nighttime data, respectively. However, the measured trends were found to be somewhat smaller if version 4.1 of the Pathfinder data was used, or if the time series of data ended earlier. The influence of El Niño on global temperatures can be seen clearly in the data. However, it was not found to affect the trend measurements significantly. Evidence of cool temperatures after the eruption of Mount Pinatubo in 1991 was also observed.
Abstract
The trend in sea surface temperature has been determined from 20 yr of Advanced Very High Resolution Radiometer Pathfinder data (version 5). The data span the period from January 1985 to December 2004, inclusive. The linear trends were calculated to be 0.18° ± 0.04° and 0.17° ± 0.05°C decade−1 from daytime and nighttime data, respectively. However, the measured trends were found to be somewhat smaller if version 4.1 of the Pathfinder data was used, or if the time series of data ended earlier. The influence of El Niño on global temperatures can be seen clearly in the data. However, it was not found to affect the trend measurements significantly. Evidence of cool temperatures after the eruption of Mount Pinatubo in 1991 was also observed.
On 20 February 2001, a converted Russian ICBM delivered Odin, a small Swedish satellite, into low Earth orbit. One of the sensors onboard is a small Canadian spectrometer called OSIRIS. By measuring scattered sunlight from Earth's horizon, or limb, OSIRIS is able to deduce the abundance of trace gases and particles from the upper troposphere into the lower thermosphere. Designed and built on a modest budget, OSIRIS has exceeded not only its 2-yr lifetime but also all expectations. With more than a decade of continuous data, OSIRIS has recorded over 1.8 million limb scans. The complexities associated with unraveling scattered light in order to convert OSIRIS spectra into highquality geophysical profiles have forced the OSIRIS team to develop leading-edge algorithms and computer models. These profiles are being used to help address many science questions, including the coupling of atmospheric regions (e.g., stratosphere–troposphere exchange) and the budgets and trends in ozone, nitrogen, bromine, and other species. One specific example is the distribution and abundance of upper-tropospheric, lightning-produced reactive nitrogen and ozone. Arguably OSIRIS's most important contributions come from its aerosol measurements, including detection and characterization of subvisual cirrus and polar stratospheric and mesospheric clouds. OSIRIS also provides a unique view of the stratospheric aerosol layer, and it is able to identify and track perturbations from volcanic activity and biomass burning.
On 20 February 2001, a converted Russian ICBM delivered Odin, a small Swedish satellite, into low Earth orbit. One of the sensors onboard is a small Canadian spectrometer called OSIRIS. By measuring scattered sunlight from Earth's horizon, or limb, OSIRIS is able to deduce the abundance of trace gases and particles from the upper troposphere into the lower thermosphere. Designed and built on a modest budget, OSIRIS has exceeded not only its 2-yr lifetime but also all expectations. With more than a decade of continuous data, OSIRIS has recorded over 1.8 million limb scans. The complexities associated with unraveling scattered light in order to convert OSIRIS spectra into highquality geophysical profiles have forced the OSIRIS team to develop leading-edge algorithms and computer models. These profiles are being used to help address many science questions, including the coupling of atmospheric regions (e.g., stratosphere–troposphere exchange) and the budgets and trends in ozone, nitrogen, bromine, and other species. One specific example is the distribution and abundance of upper-tropospheric, lightning-produced reactive nitrogen and ozone. Arguably OSIRIS's most important contributions come from its aerosol measurements, including detection and characterization of subvisual cirrus and polar stratospheric and mesospheric clouds. OSIRIS also provides a unique view of the stratospheric aerosol layer, and it is able to identify and track perturbations from volcanic activity and biomass burning.
