The representation always involves certain simplifications and assumptions. When the computer is transmitting data, the modem is needed to modulate binary data into tones. When receiving data, the device is needed to demodulate the tones to obtain the binary data required by the computer. Since the computer must be both a transmitter and receiver of data, the modem must be able to modulate and demodulate data. Winds usually blow from land to sea in the winter, while in the summer, the flow reverses and precipitation is more common.
Monsoons are most typical in India and southern Asia.
An international agreement to drastically reduce CFC production, the Protocol was adopted in Montreal in 1987. It was significantly strengthened at a subsequent meeting in London in 1990 that called for a complete elimination of CFCs by the year 2000. The agreement was again amended by a Meeting of the Parties in Copenhagen in November 1992. MTPE See Mission to Planet Earth. A line-scanning instrument flown on Landsat satellites that continually scans the Earth in a 185 km.