No abstract

The extensive fires in southeastern Australia in January 2003 culminated in the Canberra firestorm of 18 January. The fires generated a pall of smoke that blanketed the Canberra area for the following week and affected the region for most of the following month. Analysis of Sun photometer data shows that aerosol optical depths τ500 > 7 were observed during the week following the firestorm. During the subsequent month the smoke aerosol dispersed, although background conditions (τ500 < 0.1) did not return until after significant rain in late February. Analysis of aerosol optical properties retrieved from sky radiance scans shows remarkably high single scattering albedo (ϖ440 ∼ 0.96) with only a small depression evident in the week following the firestorm. This indicates that the aerosols were significantly less absorbing than would be expected from smoke freshly generated by flaming combustion, possibly a result of inefficient combustion due to the extreme intensity of the fire, and marks them out as quite distinct from the more absorbing biomass burning aerosols encountered in the savannas of tropical Australia. The high single scattering albedo gave rise to mean radiative forcings of −50 W m−2 at the top of the atmosphere and −172 W m−2 at the surface during the week following the firestorm. Maximum heating rates are depressed by a factor of two at ϖ440 = 0.96 compared with ϖ440 = 0.88. Nevertheless, for plausible atmospheric profiles the large optical depths caused heating rates peaking at more than 10 K/day near the top of the smoke layer. The layer stabilized the lower troposphere through a combination of reduced surface heating and a positive gradient in heating rate through most of the layer. The enhanced stability suppressed surface temperatures and winds during the week following the firestorm, reducing the risk of renewed fire danger, and suggesting a useful role for aerosol effects in weather prediction models.

Abstract. Collocated sun photometer and nephelometer measurements at Tinga Tingana in the Australian Outback over the decade

We have observed strong correlations between simultaneous and co‐located measurements of aerosol optical depth and column amounts of carbon monoxide, hydrogen cyanide, formaldehyde and ammonia in bushfire smoke plumes over SE Australia during the Austral summers of 2001/2002 and 2002/2003. We show how satellite‐derived aerosol optical depth maps may be used in conjunction with these correlations to determine the total amounts of these gases present in a fire‐affected region. This provides the basis of a method for estimating total emissions of trace gases from biomass burning episodes using visible radiances measured by satellites.

Clinicians increasingly use empirically based cognitive-behavioral techniques in their treatment of child victims of sexual abuse. Attribution retraining is often a primary component of this work, and it involves various techniques aimed at decreasing abuse-related self-blame and encouraging the child to attribute responsibility for the abuse to the perpetrator This article reviews literature that highlights the complexity of self and other blame for sexually abused children in terms of developmental status, the multifaceted nature and interrelationships of abuse-specific attributions, and the psychological effects of self-blame and perpetrator blame. A review of written attribution retraining techniques developed by diverse authors for use with sexually abused children and their nonoffending parents is provided, including written and verbal techniques and techniques using games and the arts. The relative utility of different approaches with children of various stages of development is discussed, along with the need for empirical research regarding the effectiveness of these techniques.