Estimating the Evaporation from Irrigation Canals in Northwestern China Using the Double-Deck Surface Air Layer Model

Table 1

General descriptions of the instruments installed at station COp1.

Variables	Instruments	Interval (min)	Height above water surface (m)
Air temperature & humidity	HMP45AC (VAISALA)	5	2 and 0.45
Wind speed	010C-1 (MET ONE)	5	2.45
Radiation	CNR4	5	0.2
Water temperature & flow speed	Glass thermometer & Flowatch (NTECH)	30 or 60	See text
Water level	HOBO	5	—