کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
6537450 | 158330 | 2015 | 6 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Nocturnal intermittency in surface CO2 concentrations in sub-Saharan Africa
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موضوعات مرتبط
مهندسی و علوم پایه
علوم زمین و سیارات
علم هواشناسی
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چکیده انگلیسی
An exploratory study of CO2 concentrations and fluxes was conducted during 2013, at a site 12Â km North of Harare, Zimbabwe. CO2 measurements were made over four adjacent fields of differing surface vegetation. The data illustrate the role of atmospheric intermittency as a mechanism for transferring CO2 between the surface and the atmosphere. At night, limited atmospheric mixing permits CO2 concentrations to increase to levels well above those conventionally reported (exceeding a spatial average of 450Â ppm on some nights), but these high levels are moderated by a periodic intermittency that appears similar to that observed elsewhere and often associated with the presence of strong, synoptic-scale winds aloft (especially low-level jets). The availability of CO2 data with adequate time resolution facilitates investigation of the general behavior, which is suspected to be a common although rarely observed feature of the lower terrestrial atmosphere. If true, this means that the nocturnal vertical transfer of momentum, heat and mass is not solely through a constrained spectral continuum of turbulence as much as by intermittent bursts, propagating from above and penetrating the surface boundary layer.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Agricultural and Forest Meteorology - Volume 200, 15 January 2015, Pages 129-134
Journal: Agricultural and Forest Meteorology - Volume 200, 15 January 2015, Pages 129-134
نویسندگان
B.B. Hicks, D.L. O'Dell, N.S. Eash, T.J. Sauer,