Stratospheric HTO and &lt;sup&gt;95&lt;/sup&gt;Zr residence times

Mason, Allen S.; Hut, G.; Telegadas, K.

doi:10.3402/tellusa.v34i4.10823

Cited by 21 publications

(11 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Finally, there was a larger test on 27.6.1973, which could have influenced the balloon data. It released 19 MCi HTO, 95% of which remained below 20 km altitude [ Mason et al , 1982]. Much of that HTO had been removed before the date of the first balloon flight on 14.6.1975, such that the impact of that test explosion on these data should have been a factor of 10 lower than that of the explosion on 17.11.1976 on those obtained from the flight on 14.8.1977, i.e., it should be negligible.…”

Section: Discussionmentioning

confidence: 99%

“…The reason probably is that the initial radioactive cloud of these explosions remained below 20 km altitude and further, that the lower stratosphere at mid latitudes is rapidly flushed by exchange with the troposphere. For example, Mason et al [1982] found that the HTO injected by the test explosion in 1976 was removed from the lower stratosphere with an e‐fold time of 1.2 years. As a consequence, only a small fraction of the so‐injected HTO penetrated to higher altitudes.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Tritiated water vapor in the stratosphere: Vertical profiles and residence time

et al. 2002

View full text Add to dashboard Cite

The historic and partly unpublished measurements of the tritium content in stratospheric water vapor made at the National Center for Atmospheric Research between 1975 and 1983 are reanalyzed. The resulting vertical profiles of the T content, mainly at 32°N latitude, show little variation with altitude above 20 km but a strong decay with time. This decay is a consequence of the large T injections into the stratosphere by the atmospheric tests of high‐yield thermonuclear devices prior to 1963 and seems to proceed with a single e‐fold time of 5.12 years. Correcting for the radioactive decay of HTO within the stratosphere and for a temporal increase in stratospheric H2O, we obtain a decay time for stratospheric HTO of 7.7 ± 2.0 years. This decay time, which is solely due to the transport of HTO into the troposphere, is much longer than the age of stratospheric air at these altitudes or the accepted values for stratospheric residence times. The differences are discussed and resolved by interpreting the HTO decay time as the Eigentime of the longest‐lived mode of the stratospheric transport equations. This Eigentime should provide a useful constraint in modeling stratospheric transport.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Tritiated water vapor in the stratosphere: Vertical profiles and residence time

et al. 2002

View full text Add to dashboard Cite

show abstract

“…It has been observed that a major removal process is by transport to polar latitudes and deposition via subsidence onto the polar ice caps [Hammer et al, 1980]. Mason et al [1982] suggest stratospheric residence times of 13.7 and 14.6 months for 95Zr and tritiated water (HTO), respectively, from Chinese nuclear weapons tests. The amount of material and its relative distribution among ash, sulfate, and sulfurous precurser gases will also affect the removal rate to the extent that there are corresponding variations in aerosol size distributions.…”

Section: Stratospheric Sulfate Aerosol Removal Ratementioning

confidence: 99%

A decade of stratospheric sulfate measurements compared with observations of volcanic eruptions

Sedlacek¹,

Mroz²,

Lazrus³

et al. 1983

J. Geophys. Res.

View full text Add to dashboard Cite

Sulfate aerosol concentrations in the stratosphere have been measured for 11 years (1971–1981) using portions of filters collected by the Department of Energy's High Altitude Sampling Program. Data collected seasonally at altitudes between 13 km and 20 km spanning latitudes from 75°N to 51°S are reported. These data are compared with the reported altitudes of volcanic eruption plumes during the same decade. From this comparison it is concluded that (1) several unreported volcanic eruptions or eruptions to altitudes higher than reported did occur during the decade, (2) the e‐fold removal time for sulfate aerosol from the stratosphere following the eruption of Volcan Fuego in 1974 was 11.2±1.2 months, (3) the volcanic contribution to the average stratospheric sulfate concentration over the decade was greater than 50%, and (4) there may be evidence for an anthropogenic contribution to stratospheric sulfate that increases at the rate of 6 to 8% per year.

show abstract

“…Another condition may be in the presence of large amount of airborne particles in the lower stratosphere and AME layer which is injected by recent volcanic activities. In this connection, Mroz et al (1983) Mason (1985) suggests that a more likely reason for the faster removal of HTO is alternation of the stratosphere-troposphere exchange rate by the radiative effect of the sulfate aerosol injected into the stratosphere by large-scale volcanic eruptions. The heating of the atmosphere in the 30mb region as a result of the additional volcanic aerosol after the E1 Chichon eruption has been reported by Quiroz (1983) and at 30 and 50mb by Labitzke et al (1983).…”

Section: Comparison Between the Calculated Andmentioning

confidence: 99%

“…Mason (1985) has observed that the depletion of the HTO burden in the stratosphere in 1982 showed an anomalous rate in comparison with other years which has the apparent characteristic time of 7.8 months, roughly half of the normal residence time. The transport process involving such a short residence time cannot be explained by a simple scavenging model with the apparent residence time of about one year.…”

Section: Introductionmentioning

confidence: 99%

Annual Deposition of Sr-90, Cs-137 and Pu-239, 240 from the 1961-1980 Nuclear Explosions: A Simple Model

Hirose¹,

Aoyama²,

Katsuragi³

et al. 1987

Journal of the Meteorological Society of Japan

View full text Add to dashboard Cite

The annual deposition of 240, and Pu-238 were observed from 1959 to 1984 at the Meteorological Research Institute (MRI). In order to interpret the serial trends of the annual radioactive deposition at the MRI, a semi-empirical box model of atmospheric transport was developed. The model divides the atmosphere of the Northern Hemisphere into four compartments: the atmosphere above 21km, stratosphere below 2.1km, active mixing and exchange (AME) layer near the tropopause, and the troposphere. The transfer between the compartments follows the firstorder kinetics. The half residence times for transfer between upper and lower stratospheric compartments, between the lower and AME layer compartments, and between the AME layer and troposphere are 0.5, 0.7 and 0.3yrs, respectively. It is revealed that as a long-term monitoring of the annual deposition of radioactive debris in the mid-latitude area, the model quantitatively permits the calculation of stratospheric inventories and trends of annual deposition of debris injected into the stratosphere which are characterized by apparent residence times of 0.5 to 1.7yrs. This simple model is useful to predict the annual deposition amount of radioactive debris from the thermonuclear explosion for practical purposes.

show abstract

Stratospheric HTO and <sup>95</sup>Zr residence times

Cited by 21 publications

References 4 publications

Tritiated water vapor in the stratosphere: Vertical profiles and residence time

Tritiated water vapor in the stratosphere: Vertical profiles and residence time

A decade of stratospheric sulfate measurements compared with observations of volcanic eruptions

Annual Deposition of Sr-90, Cs-137 and Pu-239, 240 from the 1961-1980 Nuclear Explosions: A Simple Model

Contact Info

Product

Resources

About