| Author | Gauri Shanker Bassi |
| Call Number | AIT Thesis no. WA-92-9 |
| Subject(s) | Meteorological stations--China
|
| Note | A thesis submitted in partial fulfillment of the requirements for the Degree of Master of Engineering, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Abstract | This study attempts to develop relationships between the meteorological instruments manufactured
and used in People's Republic of China and the standard instruments installed in the IREM (Irrigation
Engineering And Management) programme weather station at AIT.Two different environments, one
synchronized with standard equipments and another with obstruction, a structure made up of OJ.pipe,
wiremesh and plastic sheets (3mx3m), were in,vestigated.
Most of the old and new instruments were calibrated in the calibration laboratory at Bang Na,
Bangkok Thailand before their installations and measurements.
Chinese instruments were related to the existing standard instruments and Chinese instruments with
obstructions. In most cases good correlation were found. Chinese evaporation pans showed good
correlation with standard Class A pan and Chinese small pans w.ith obstructions. It was also found
insignificant correlation of Class A pan with Colorado sunken pan arid the RID pan in the study. Chinese
raingauges with and without obstruction showed good correlation with standard raingauge except the one
installed at 'E' obstructed from west:direction.
Error analysis indicated excess evaporation by Chinese small pans (both under standard and
obstructed condition) than Standard Class A pan. Excess evaporation of 2.2mm (i.e. 28%) in case of pan
under standard condition with respect to standard class A pan was found . variation from 2. lmm
(i.e.19.6%) to 1.03mm (i.e.10.4%) less evaporation in case of obstructed pans with respect to similar
Chinese pan under standard condition were observed.
Among the Chinese raingauges with obstructions maximum reduced raincatch of 3.6mm (i.e.
30.7%) by the raingauge on location 'E' obstructed from west direction with respect to similar gauge
under standard condition were found for the period of study (1 April to 15 June 1992). Chinese and
standard raingauges under same standard condition observed nearly the same.
Observed data from Chinese instruments were used in different empirical formulae which were
applied to find evapotranspiration (Eto) separately. Relative error and absqlute error for Eto computed as
above and by Class A pan also indicated high evaporation by Chinese instruments than by Class A pan.
High evaporation and less raincatch implied that there would be underestimation of change in
water storage in water balance study using Chinese instruments.
It is also found that Chinese instruments (weather station) were seven times cost effective than
the standard instruments. |
| Year | 1992 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Water Resources Research Engineering (WA) |
| Chairperson(s) | Loof, Rainer
|
| Examination Committee(s) | Koga, Kiyoshi ;Onta, Pushpa Raj
|
| Scholarship Donor(s) | German Academic Exchange Service (DAAD)
Federal Republic of Germany |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1992 |