This study attempts to investigate the distribution of ventifacts in Qatar. It is believed that ventifacts are confined to the areas within about 5 km of the Miocene or Mio-Pliocene Hofuf formations and the spreads of continental gravels derived from them. Three hypotheses were formulated: (1) Ventifacts in Qatar are confined to areas within about 5 km of the Hofuf formations and the spreads of continental gravels derived from them. The distribution of ventifacts within these areas varies according to the nature of the ground surface; (2) The most active ventifaction areas are where the continental gravels merge with the Eocene limestone because of the increase in saltation particle speed in these areas where bedrock or bare limestone is exposed; (3) The unit area ratio of ventifact to non-ventifact pebbles varies inversely with the total amount of pebbles. To test these hypotheses, nine land class categories were identified in the three major Hofuf formations. Line transects were carried out from randomly selected stations near the middle of the Hofuf formations. Along each transect systematic sampling was carried out at 200 m intervals. The data were processed using a WANG MVP 2200 computer with software developed for the project. It was found that ventifacts tend to concentrate on the outer edges of the continental gravels in areas of limestone outcrop and limestone pavement. Higher areas have big gravel counts and a low ratio of ventifacts while the low-lying plains have small gravel counts and a higher ratio of ventifacts. In certain areas 'ventifact fields' were found where the density of ventifacts was as high as 30 per m2. Many of the ventifacts in these fields were buried beneath the surface suggesting that the ventifaction predates the present site conditions. Other high ventifact density areas were discovered where the ventifacts have collected in shallow depressions or hollows on the limestone plateaux. Water action has washed these ventifacts, a high proportion of which are dreikanters, into the hollows, where they have been partially buried in fine alluvial silts. These 'ventifact graveyards' are generally only a few metres wide but contain large numbers of fine specimens.
The New York area is well-known to have some of the most congested airspace and airports in the U.S. National Airspace System (NAS). The challenge to air traffic management results from high demand, proximity of busy airports, and occasional disruptive weather events. A prototype capability called Integrated Departure Route Planning (IDRP) is being tested this year (2010), in its "Phase 1" version. It will be an adjunct capability to the Route Availability Planning Tool (RAPT), developed by the Massachusetts Institute of Technology/Lincoln Laboratory (MIT/LL), which has been used successfully in a prototype mode for several years. The IDRP display windows will be output onto the RAPT terminal device, which is now installed at the New York approach control, several en route centers, multiple towers, and several air carrier operations desks.IDRP provides a forecast horizon of fix-and route-specific loading for New York departures, with color-coding to alert traffic managers about fix congestion and possible weather impacts. Whereas the RAPT display shows route blockage/availability and is useful only in situations of convective weather, IDRP should have benefits during both good weather and convective activity.A benefits estimation process was undertaken to approximate the total annual dollar benefit that might be expected from the full deployment of IDRP (which is some years away) to deal with nonweather-related congestion. Analysis of archived data found cases where fix congestion, and the associated taxi-out delays could have been ameliorated by reassigning affected flights to uncongested alternate fixes, subject to airline acceptance.
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