East Asia and Western Pacific METEOROLOGY AND CLIMATE

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start from October 1990 and end in the same month (October) of 1992.
Intensive Observing Periods CIQP) The formal observing period will
include 4 intensive observing periods, scheduled to take place in four
different seasons in 1991, each lasting 15 days. The scientific
objectives for the four lOPs are as follows:
(1) In winter (December or January), observational study on the
behaviour of the energy exchange between air and land surface, i.e.
whether the land surface is a heat sink or a heat source; and the
physical mechanisms of the energy exchange between air and land
surface when ground surface is a heat sink.
(2) In spring (April), two major scientific problems will be
studied: Air-mass transformation Atmospheric dust formation
(3) In summer (July), the main scientific objective is to observe
and study the structure of the PEL and the advection effect in the
PEL.
(4) In autumn (October), the seasonal transition of surface energy
budget*
Pilot Observing Period (]pOP) One pilot field observation was
conducted in August and September 1988 before the FOP. The aims of
the POP are to test the automatic data collecting and transmitting
system, and to carry out the field observational plan in order to
explore the scientific results and learn the logistical lessons.
VI* Measurements
(1) Measurements during JFOp Radiation — The radiation
measurements can be divided into two parts. Some are long term
measurements (lasting for two years) concerned with estimating the
radiative energy budget of the ground surface. Additional special
measurements of atmospheric and surface radiation properties are
directed towards providing corrections for satellite data. For this
reason, the measurements of the spectral solar and infrared radiations
at a well-chosen set of discrete wavelength bands should be made