Geopotential harmonics of order 15 and odd degree from analysis of resonant orbits

We have analysed the variations of inclination in 13 satellite orbits as they pass slowly, under the action of air drag, through 15th-order resonance with the geopotential, when successive equatorial crossings are 24° apart and the ground track repeats after 15 rev. The size and form of the change in inclination are determined mainly by the values of the geopotential harmonics of 15th order and odd degree, $\text{C}\text{?}{}_{\mathrm{l,15}}$ and $\text{S}\text{?}{}_{\mathrm{l,15}}$ (with l = 15, 17, 19, …) in the usual notation. Our analysis gives values of these coefficients up to l = 33 as follows:

     

102.

Editorial: The LITFASS-98 experiment     

F. Beyrich  T. Foken  H.-J. Herzog 《Theoretical and Applied Climatology》2002,73(1-2):1-2

     

103.

Middle Pleistocene molluscan and ostracod faunas from Allhallows, Kent, UK     

M.R. BatesD.H. Keen  J.E. WhittakerJ.S. Merry  F.F. Wenban-Smith 《Proceedings of the Geologists' Association. Geologists' Association》2002,113(3):223-236

     

104.

Transitions in a Globalising World     

H.J. Schellnhuber 《Global Change & Human Health》2002,3(1):73-73

     

105.

Some Aspects of Resource Uncertainty and Their Economic Consequences in Assessment of the 1002 Area of the Arctic National Wildlife Refuge     

Attanasi  Emil D.  Schuenemeyer  John H. 《Natural Resources Research》2002,11(2):109-120

Natural Resources Research - Exploration ventures in frontier areas have high risks. Before committing to them, firms prepare regional resource assessments to evaluate the potential payoffs. With...     

106.

A method to reduce the influence of ice-rafted debris on a grain size record from northern Fram Strait, Arctic Ocean   总被引：2，自引：0，他引：2  

H. Christian Hass 《Polar research》2002,21(2):299-306

The granulometric composition of terrigenous deep-sea sediments provides information on current speed if certain frame conditions are fulfilled. These include that current transport is the only transport process. At high latitudes this type of investigation is impaired due to the influence of ice-rafted debris (IRD) which contaminates the current-sorted grain size fractions. This study presents a new method that addresses this problem by setting the ice-rafted sand in relation to the silt of both current- and ice-transported origin. Deviations from the resulting regression function are then used to determine the behaviour of the silt mean grain size as a function of current speed largely independent from IRD bias. The study is based on sediments from the Yermak Plateau, Arctic Ocean, a region influenced by IRD brought with the south-headed Transpolar Drift and by north-directed bottom currents. The IRD correction results in displaying changes of current speed at much higher clarity; climate forcing of the currents becomes more evident. For example, the 8200 year cold event shows up as a major event in the corrected record whereas it is hardly visible in the original record.     

107.

Bent-ray traveltime tomography and migration without ray tracing     

P. E. Ecoublet  S. C. Singh  C. H. Chapman  G. M. Jackson 《Geophysical Journal International》2002,149(3):633-645

     

108.

Shear wave statics using receiver functions   总被引：1，自引：0，他引：1  

D. van Manen  J. O. A. Robertsson  A. Curtis  R. Ferber  H. Paulssen 《Geophysical Journal International》2003,153(3):F1-F5

     

109.

Inferring erosional resistance of bedrock units in the east Tennessee mountains from digital elevation data     

Hugh H. Mills   《Geomorphology》2003,55(1-4):263

Measures of local relief, regional relief, and slope were calculated from digital elevation models (DEMs) for 50 bedrock units in the Ridge and Valley and Blue Ridge provinces of Tennessee. Each of these measures was normalized and the three were then averaged to produce the erosional resistance index (ERI). Bedrock units with higher ERI values include coarse clastics, intermediate clastics, and metaplutonics. Units with lower values include shales, limestones, limestones plus dolostones, and carbonates plus fine clastics. Dolostones tend to have intermediate values. The calculated ERI values were compared with subjective ratings by a geologist with decades of field experience in east Tennessee. Generally, the agreement between the two ratings was good, the most glaring exception being several shales with improbably high ERI values. These turned out to be thin units cropping out beneath very hard sandstones, allowing them to stand higher and steeper than would otherwise be possible. A systematic method for detecting such erroneously high ERI values is suggested. Inspection of a drainage map superimposed on the geology map shows that in a given area, streams tend to flow on rock units with the lowest ERI values. In addition, statistical analysis shows that bedrock units with the lowest ERI values are, on average, almost three times closer to the nearest stream and six times as likely to have streams flowing on them than are units with highest values. Further, the effect of ERI on stream location is strongest for streams with drainage areas between 1 and 30 km². Thus, small streams appear to be subject to greater lithologic control than are larger streams.     

110.

Recent Changes in the Climate At the Dead Sea – a Preliminary Study     

P. Alpert  H. Shafir  D. Issahary 《Climatic change》1997,37(3):513-537

In the last decade pan evaporation measured at the Southern Dead Sea has significantly increased. Wind, temperature and humidity measurements at the Dead Sea starting in the 1930s as well as 3-D model simulations all seem to indicate a statistically significant change in the local climate of the Dead Sea region. The potential contribution to this climatic change through the weakening of the local land-sea breeze circulation caused by the reduction in the Dead Sea surface area in 1979–1981, is examined. It is suggested that since the breeze tempers the Dead Sea climate, its weakening has caused the air temperature to increase, the relative humidity to decrease and thus increased the pan evaporation. The climatic changes as implied by the MM4 Mesoscale PSU/NCAR model simulations, seem to fit the observed changes and to suggest a local tendency to the more arid climate that now prevails to the south of the study region.     

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l	109C?l,15	109S?l,15
15	?23.5 ± 0.8	?7.7 ± 0.8
17	6.3 ± 1.5	5.6 ± 1.5
19	?25.1 ± 2.5	?7.3 ± 2.3
21	27.8 ± 3.6	?0.7 ± 3.4
23	17.1 ± 4.1	13.9 ± 4.8
25	?1.1 ± 3.0	8.5 ± 4.2
27	10.0 ± 3.3	6.7 ± 2.7
29	?9.4 ± 3.5	0.1 ± 4.7
31	10.1 ± 5.4	3.8 ± 5.6
33	1.1 ± 5.7	3.1 ± 5.8

Some Aspects of Resource Uncertainty and Their Economic Consequences in Assessment of the 1002 Area of the Arctic National Wildlife Refuge

Natural Resources Research - Exploration ventures in frontier areas have high risks. Before committing to them, firms prepare regional resource assessments to evaluate the potential payoffs. With...     

A method to reduce the influence of ice-rafted debris on a grain size record from northern Fram Strait, Arctic Ocean

The granulometric composition of terrigenous deep-sea sediments provides information on current speed if certain frame conditions are fulfilled. These include that current transport is the only transport process. At high latitudes this type of investigation is impaired due to the influence of ice-rafted debris (IRD) which contaminates the current-sorted grain size fractions. This study presents a new method that addresses this problem by setting the ice-rafted sand in relation to the silt of both current- and ice-transported origin. Deviations from the resulting regression function are then used to determine the behaviour of the silt mean grain size as a function of current speed largely independent from IRD bias. The study is based on sediments from the Yermak Plateau, Arctic Ocean, a region influenced by IRD brought with the south-headed Transpolar Drift and by north-directed bottom currents. The IRD correction results in displaying changes of current speed at much higher clarity; climate forcing of the currents becomes more evident. For example, the 8200 year cold event shows up as a major event in the corrected record whereas it is hardly visible in the original record.     

Inferring erosional resistance of bedrock units in the east Tennessee mountains from digital elevation data

Measures of local relief, regional relief, and slope were calculated from digital elevation models (DEMs) for 50 bedrock units in the Ridge and Valley and Blue Ridge provinces of Tennessee. Each of these measures was normalized and the three were then averaged to produce the erosional resistance index (ERI). Bedrock units with higher ERI values include coarse clastics, intermediate clastics, and metaplutonics. Units with lower values include shales, limestones, limestones plus dolostones, and carbonates plus fine clastics. Dolostones tend to have intermediate values. The calculated ERI values were compared with subjective ratings by a geologist with decades of field experience in east Tennessee. Generally, the agreement between the two ratings was good, the most glaring exception being several shales with improbably high ERI values. These turned out to be thin units cropping out beneath very hard sandstones, allowing them to stand higher and steeper than would otherwise be possible. A systematic method for detecting such erroneously high ERI values is suggested. Inspection of a drainage map superimposed on the geology map shows that in a given area, streams tend to flow on rock units with the lowest ERI values. In addition, statistical analysis shows that bedrock units with the lowest ERI values are, on average, almost three times closer to the nearest stream and six times as likely to have streams flowing on them than are units with highest values. Further, the effect of ERI on stream location is strongest for streams with drainage areas between 1 and 30 km². Thus, small streams appear to be subject to greater lithologic control than are larger streams.     

Recent Changes in the Climate At the Dead Sea – a Preliminary Study

In the last decade pan evaporation measured at the Southern Dead Sea has significantly increased. Wind, temperature and humidity measurements at the Dead Sea starting in the 1930s as well as 3-D model simulations all seem to indicate a statistically significant change in the local climate of the Dead Sea region. The potential contribution to this climatic change through the weakening of the local land-sea breeze circulation caused by the reduction in the Dead Sea surface area in 1979–1981, is examined. It is suggested that since the breeze tempers the Dead Sea climate, its weakening has caused the air temperature to increase, the relative humidity to decrease and thus increased the pan evaporation. The climatic changes as implied by the MM4 Mesoscale PSU/NCAR model simulations, seem to fit the observed changes and to suggest a local tendency to the more arid climate that now prevails to the south of the study region.