Energy balance of a suburban vegetated area in a tropical city--Delhi (India).
Energy balance measurements were carried out in a suburban vegetated area of southern part of Delhi. These measurements were made on several days during winter (January, February, November, December) and summer (April, May, June) of 1998 and 1999, respectively. During the winter 1998, net radiation (Q*) reached up to 108 W/m2 around noon and during the summer 1999, Q* was as high as 423.43 W/m2. The apportionments of Q* into sensible heat (H) and latent heat (LE) fluxes were 63% and 16% respectively during the summer 1998, whereas, during the winter Q* dissipated by 40% and 60%, respectively by H and LE. Similarly, during the summer 1999, partitioning of Q* into H and LE were 52 and 24%, respectively and during the winter, apportionments of H and LE found to be 37% and 39% respectively. On an average, about 34% of Q* was dissipated as soil heat flux (G) during both the summers (1998 and 1999) and the winter 1999, whereas, during the winter 1998, G was about 14% of Q*. Diurnal variations of H and LE showed erratic nature whereas that of G was relatively smoother during both the summers and winters. The calculated Bowen ratio was 0.67 to 0.91 during winters and 2.16 to 3.84 during summers, respectively. Probably, seasonal differences are due to local/synoptic conditions, nature of sub stratum and existence of vegetation, which influence the energy partitioning. However, as there was no surplus of energy, the area acts as a heat sink.
Das
Yashvant
Y
Science and Engineering Research Council-DST, Centre for Atmospheric Sciences, Indian Institute of Technology Delhi, New Delhi-110016. yashvantdas@hotmail.com
Padmanabhamurty
B
B
D002947:Cities; D017753:Ecosystem; D004734:Energy Metabolism; D006358:Hot Temperature; D007194:India; D010944:Plants / Q000378:metabolism; D011834:Radiation Monitoring; D012621:Seasons; D012987:Soil; D013997:Time Factors
D012987:Soil