Search results
Results from the WOW.Com Content Network
Temperature differences can cause air currents because warmer air is less dense than cooler air, causing the warmer air to appear "lighter." Thus, if the warm air is under the cool air, air currents will form as they exchange places. Air currents are caused because of the uneven heating of Earth's surface. [5] [6]
The rising air creates a low pressure zone near the equator. As the air moves poleward, it cools, becomes denser, and descends at about the 30th parallel, creating a high-pressure area. The descended air then travels toward the equator along the surface, replacing the air that rose from the equatorial zone, closing the loop of the Hadley cell. [3]
This current is carried by ions present in the atmosphere (generated mainly by cosmic rays in the free troposphere and above, and by radioactivity in the lowest 1km or so). The ions make the air weakly conductive; different locations, and meteorological conditions have different electrical conductivity.
Area control centers (ACCs) control IFR air traffic in their flight information region (FIR). The current list of FIRs and ACCs is maintained by the International Civil Aviation Organization (ICAO). The following is the alphabetic list of all ACCs and their FIRs as of October 2011:
A valley exit jet is a strong, down-valley, elevated air current that emerges above the intersection of the valley and its adjacent plain. These winds frequently reach speeds of up to 20 m/s (72 km/h; 45 mph) at heights of 40–200 m (130–660 ft) above the ground.
This is a list of countries and territories by the United Nations geoscheme, including 193 UN member states, two UN observer states (the Holy See [note 1] and the State of Palestine), two states in free association with New Zealand (the Cook Islands and Niue), and 49 non-sovereign dependencies or territories, as well as Western Sahara (a disputed territory whose sovereignty is contested) and ...
This page was last edited on 26 November 2022, at 23:40 (UTC).; Text is available under the Creative Commons Attribution-ShareAlike 4.0 License; additional terms may apply.
This is a list of articles holding galleries of maps of present-day countries and dependencies. The list includes all countries listed in the List of countries, the French overseas departments, the Spanish and Portuguese overseas regions and inhabited overseas dependencies. See List of extinct countries, empires, etc. and Former countries in ...