HUMAN ACTIVITIES ALTER HYDROLOGICAL CYCLE

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HUMAN ACTIVITIES ALTER HYDROLOGICAL CYCLE

• TANG QIUHONG

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Human activities alter hydrological cycle

• Introduction
• Research area
• Some ideas

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Human Domination of Earths Ecosystems1
Human alteration of earth is substantial and
growing.
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Human activities hydrological cycle2,3,4
Land transformation
Intake from river, reservoir

• Most of human activities that alter
  rainfall-runoff flow is unconscious.
• The actions people manage water resources are the
  actions people try to influence dissipative flow.

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Focus on Dissipative Flow
1.Natural Dissipative flow (without human
interpose)

• Flow or seepage to lowland because of hydraulic
  head without human interpose
• To simulate NDF we need know groundwater,
  elevation well. But the inability to describe
  heterogeneity in aquifer characteristics is a
  fundamental problem in groundwater hydrology and
  will continue.6

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2.Manmade Dissipative flow (direct human
interpose)
70 of man-used water is used in agriculture7
River
Soil water
City
Soil water
Groundwater
Groundwater
irrigated land
NON-irrigated land
Use population, economic growth etc to estimate
it . (about 30)
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Visualization
(Modified from Illinois Water Resources Center
(IWRC) 8)
Runoff flow (direct) Surface runoff is lagged by
ridge of field. Dissipative flow
(direct) Keeping soil moist when it is
dry. ltindirectgt Human activities affect latent
and sensible fluxes to the atmosphere. Feedback
to atmosphere (evaporation, albedo, etc)
Feedback
E
P
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Human activities alter hydrological cycle

• Introduction
• Research area
• Some ideas

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Scale

• We need to incorporate the mechanics of soil
  moisture redistribution, and this demand us to
  predicate the response of this system on a
  timescale not long.
• Type of soil and vegetation should be specified
  (We need to consider groundwater because a
  shallow water table provides moisture for the
  soil and vegetation and such acts as a source
  term for evapotranspiration to the atmosphere9.
  Of cause, because of the inability to know
  spatial heterogeneity, we should simplified it ).
  This limits the spatial scale.
• Research area a catchment (Yellow River)
• Timescale month (timestep days/hours)

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Why We Choose Yellow River
We should choose a river basin in semiarid
area. arid area no efficient runoff flow(e.g.
Tarimu River ) humid area dissipative flow is
not remarkable
perennial
perennial
Fig 1. Comparison between precipitation of 1998
and perennial in Yellow River10 Fig 2.
Comparison between streamflow of 1998 and
perennial in Yellow River 10
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Human activities alter hydrological cycle

• Introduction
• Research area
• Some ideas

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Model description(??)

• Coupling with atmosphere
• Physically base on Soil water model
• Consider Groundwater
• Watershed-scale

? Horizontal boundary conditions Given by a large
scale model (GCM or a nested grid model)
(pressure, humidity, temperature, wind gradients
) ? Internal Cycle (Timestep hours or
less?) To calculate (atmosphere radiation, wind
speed, pressure, humidity, temperature, and
precipitation)
(FAO) Penman-Monteith equation
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Model description(??)
? Atmosphere-Soil interaction 1.Atmosphere model
gives parameters for Penman-Monteith equation -gt
Evaporation (latent heat flux) 2. Atmospheric
radiation -gt sensible heat flux land use
type ? Root zone water balance
Irrigation (soil moisture)
P
P
Et
hortonian overland flow
Soil water
Soil water
saturation overland flow( water table rises
above the land surface)
Groundwater
Groundwater
irrigated land
NON-irrigated land
Evapotranspiration from water table If water
table depth gt5m, it is zero.
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Model description(?)
? Groundwater balance
Soil water
Soil water
Exchange
River
Groundwater
Groundwater
irrigated land
NON-irrigated land
Exchange f(water level,water table) ? depended
on elevation
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Model description(total)
grid of large scale model
?
Cycle in atmosphere (interaction)
Penman-Monteith equation (no data) Groundwater
(initial water table) given by repeatedly
running the model (not sure) Riverway storage
(including reservoir, lake) we should give a
simple operation rule on it12.
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Next step
Specify the research area Collect dataset Coding
,put it into action
(from Tsinghua Alumni Association Website, URL
http//www.tsinghua.org.cn/ )
????
Acts speak louder than words.
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Acknowledge
Some of the ideas come from reference 9 and
12. Also I would like to appreciate my
supervisor Dr. HU Heping in Tsinghua University,
Beijing China for references 234.
Reference

• 1 Vitousek et al., Human Domination of Earth's
  Ecosystems, Science 1997 277 494-499
• 2 ?????????????? I????,???,???, ???, ?????
  (???)(in Chinese)HU Heping, TANG Qiuhong, and
  TIAN Fuqiang. A Dissipative Hydrological Model
  for Arid Plain Oasis, I Model Structure, Advance
  in water science, (in press)
• 3 ?????????????? II????,???, ???,???, ?????
  (???)(in Chinese)TANG Qiuhong, TIAN Fuqiang, and
  HU Heping. A Dissipative Hydrological Model for
  Arid Plain Oasis, II Applications of Model,
  Advance in water science, (in press)
• 4 ??????????????, ???,???, (in Chinese, English
  version is under construction) HU Heping, TANG
  Qiuhong. A Study of Hydrological Model Based on
  Dissipative Flow, (personal document).
• 5 The Environment in Tokyo - Aquatic
  Environment 2/2. URL http//www.kankyo.metro.toky
  o.jp/kouhou/english2001/we_2.htm
• 6 Alley et al., Flow and Storage in Groundwater
  Systems, Science 2002 296 1985-1990
• 7 Human Appropriation of Renewable Fresh Water
  ,Sandra L. Postel, Gretchen C. Daily, and Paul R.
  Ehrlich , Science 9 February 1996 271 785-788
  (in Reports).
• 8 Website of Illinois Water Resources Center
  (IWRC) URL http//www.environ.uiuc.edu/iwrc/faq.h
  tm

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Reference (continued)

• 9 York, J. P., M. Person, W.J. Gutowski and T.
  C. Winter, 2002 Putting aquifers into
  atmospheric simulation models An example from
  the Mill Creek Watershed, northeastern Kansas.
  Adv. Wat. Res., 25, 221-238.
• 10 ???????, ?????????? (in Chinese) Bulletin of
  Yellow River water resources, Yellow River
  Conservancy Commission, ministry of water
  resources of the Peoples Republic of China.
• 11 Gutowski, W. J., C. J. Vorosmarty, M.
  Person, Z. Otles, B. Fekete and J. York, 2002 A
  Coupled Land-Atmosphere Simulation Program
  (CLASP). J. Geophys. Res., 107 (D16),
  4283,10.1029/2001JD000392
• 12 Chong LI, Dawen YANG, Guangheng NI and
  Heping HU, 2004 Simulation of irrigation
  consumption in the Yellow River basin using a
  distribution hydrological model. (in press,
  personal communication)