Problems in the research of arid and semi-arid area

From the above sections, the followings are pointed out:

• the precipitation amount are locally different, especially dependent on its altitude, though the disturbances causing it are of large scale,

• the oasis evapotranspiration is very large and the dominant term of the water consumption,

• the irrigation and the dry air over oasis are very important terms, which controls oasis water budgets,

• the desert evaporation may also consume water,

• the ground water has a significant roll in water budget especially to the time delay,

• to investigate the turbulent transfer process over desert area can be one of the good challenge to brush up the knowledge of the turbulent transfer process.

And also the water vapor movement between mountains and bottoms, or its advection may be important, which was not mentioned above.

I personally want to emphasize the importance to research turbulent transfer process, because it might to improve the modeling of surface process. If it can be understand as the continuous process to the local circulation, large convection, or advection, the Monin-Obukhov similarity could be improved after 60 year using.

But to know the water cycle, the measurements on oasis are the most important one, as well as on river flow. It needs to include the measurement of irrigation and of the dry air advection from surrounding desert. There we need to apply some numerical modeling and an observation network to investigate the oasis surrounded by desert. Also the water quality measurement can make good contribution to understand water movement.