Search Results - "Hargreaves, K J"

Linking land-atmosphere-stream carbon fluxes in a lowland peatland system by Billett, M.F, Palmer, S.M, Hope, D, Deacon, C, Storeton-West, R, Hargreaves, K.J, Flechard, C, Fowler, D

“…Any change in the ability of northern peatlands to act as a sink for atmospheric CO2 will play a crucial part in the response of the Earth system to global…”
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Auroral radio absorption: The prediction question by Hargreaves, J.K.

“…The paper summarises key facts and figures about the phenomenon of auroral radio absorption which are relevant to the problem of predicting its occurrence and…”
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On the fine structure of medium energy electron fluxes in the auroral zone and related effects in the ionospheric D-region by HARGREAVES, J. K, BIRCH, M. J, EVANS, D. S

“…This study is based on measurements of trapped and precipitated electrons of energy >30 keV and >100 keV observed by polar orbiting environmental satellites…”
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A new method of studying the relation between ionization rates and radio-wave absorption in polar-cap absorption events by HARGREAVES, J. K

“…During polar-cap absorption events, which are caused by the incidence of energetic solar protons, the high-latitude ionospheric D region is extended down to…”
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Quasi-periodic ripples in high latitude electron content, the geomagnetic field, and the solar wind by Birch, M. J., Hargreaves, J. K.

“…In this study we present evidence for the existence of quasi-periodic ripples in the F-region electron content at high latitude, the magnetic flux density at…”
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Ammonia fluxes in relation to cutting and fertilization of an intensively managed grassland derived from an inter-comparison of gradient measurements by Milford, C., Theobald, M. R., Nemitz, E., Hargreaves, K. J., Horvath, L., Raso, J., Dämmgen, U., Neftel, A., Jones, S. K., Hensen, A., Loubet, B., Cellier, P., Sutton, M. A.

“…Quantification of ammonia (NH3) land-atmosphere exchange is required for atmospheric modelling and assessment of nitrogen deposition, yet flux measurement…”
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Annual methane emission from Finnish mires estimated from eddy covariance campaign measurements by HARGREAVES, K. J, FOWLER, D, PITCAIRN, C. E. R, AURELA, M

“…Measurements of landscape-scale methane emission were made over an aapa mire near Kaamanen in Finnish Lapland (69 degree 8' N, 27 degree 16' E, 155 m ASL)…”
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Development of a low-cost system for measuring conditional time-averaged gradients of SO2 and NH3 by Famulari, D., Fowler, D., Nemitz, E., Hargreaves, K. J., Storeton-West, R. L., Rutherford, G., Tang, Y. S., Sutton, M. A., Weston, K. J.

“…A conditional time-averaged gradient (COTAG) system has been developed to provide direct long-term (weekly to monthly) average flux gradient measurements for a…”
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Intercomparison and assessment of turbulent and physiological exchange parameters of grassland by Nemitz, E., Hargreaves, K. J., Neftel, A., Loubet, B., Cellier, P., Dorsey, J. R., Flynn, M., Hensen, A., Weidinger, T., Meszaros, R., Horvath, L., Dämmgen, U., Frühauf, C., Löpmeier, F. J., Gallagher, M. W., Sutton, M. A.

“…Commonly, the micrometeorological parameters that underline the calculations of surface atmosphere exchange fluxes (e.g. friction velocity and sensible heat…”
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Seasonal variations in the incidence of auroral radio absorption events at very high latitude, and the influence of the magnetotail by HARGREAVES, J. K

“…A statistical analysis has been made of the incidence of auroral radio absorption events at South Pole, and of its dependence on basic geophysical parameters…”
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Variations in cutoff latitude during selected solar energetic proton events by Birch, M. J., Hargreaves, J. K., Senior, A., Bromage, B. J. I.

“…Proton count rate measurements were obtained from the polar orbiting environmental satellites POES15 and POES16 during three solar proton events in 2001. From…”
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Quantifying the effects of water table and soil temperature on the emission of methane from peat wetland at the field scale by Hargreaves, K.J, Fowler, D

“…Methane emissions from peat wetlands have been shown to be very sensitive to soil temperature and the position of the water table in controlled environment…”
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National inventories of terrestrial carbon sources and sinks : The U.K. experience by CANNELL, M. G. R, MILNE, R, SUBAK, S, HARGREAVES, K. J, BROWN, T. A. W, CRUICKSHANK, M. M, BRADLEY, R. I, SPENCER, T, HOPE, D, BILLETT, M. F, ADGER, W. N

“…The U.K. has extensive databases on soils, land cover and historic land use change which have made it possible to construct a comprehensive inventory of the…”
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On the relations between proton influx and D-region electron densities during the polar-cap absorption event of 28-29 October 2003 by HARGREAVES, J. K, BIRCH, M. J

“…Observations by incoherent-scatter radar have been applied to explore relationships between the fluxes of incident protons and the resulting D-region electron…”
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Methane emission rates from a northern wetland; response to temperature, water table and transport by Macdonald, J.A, Fowler, D, Hargreaves, K.J, Skiba, U, Leith, I.D, Murray, M.B

“…Static chamber measurements of CH 4 flux were made from a range of micro-environments in an area of blanket bog in Northern Scotland. CH 4 flux covered a wide…”
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D-and E-region effects in the auroral zone during a moderately active 24-h period in July 2005 by HARGREAVES, J. K, BIRCH, M. J, BROMAGE, B. J. I

“…The effects of energetic electron precipitation into the auroral region at a time of enhanced solar wind have been investigated during a continuous period of…”
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Effects of high-speed solar wind on energetic electron activity in the auroral regions during July 1–2, 2005 by Birch, M.J., Hargreaves, J.K., Bromage, B.J.I., Evans, D.S.

“…This study concerns the properties and behaviour of energetic ( > 30 keV ) electrons in the magnetosphere in relation to an enhancement of the solar wind…”
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The estimation of D-region electron densities from riometer data by Hargreaves, J. K., Friedrich, M.

“…At high latitude the hard electron precipitation associated with auroral activity is a major source of ionization for the D-region, one consequence being the…”
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THEMIS observations and riometry: A data comparison with a view to proxy and prediction by Birch, M.J., Hargreaves, J.K.

“…A comparison has been made between radio absorption events observed by riometer at selected times of day and bursts of electrons observed in the midnight…”
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Variability and spatial fine structure of precipitating and trapped medium-energy electron fluxes in the noon sector by Hargreaves, J. K., Birch, M. J., Evans, D. S.

“…The relationships between the precipitating and trapped components of magnetospheric electron flux for energy ranges exceeding 30 and 100 keV have been…”
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