WATER CYCLE AND WEATHER SCALES

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WATER CYCLE AND WEATHER SCALES
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What is weather scale?

• Meteorologists classify weather phenomena into
  four classes or scales. The four scales are
  microscale, mesoscale, synoptic scale, and global
  scale.
• Each scale has its own phenomena.

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Global scale

• Global scale
• These patterns are covering tens of thousands of
  miles and affecting large parts of the world.

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Analyse water cycle over the global
Vapor out
Vapor in
temperature, precipitation radiation ,

• To assess water resource (change)
• To assess soil erosion (change)
• To assess (change)

large spatial scale (planetary scale) long time
scale (year) imprecise result (trend, change)
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Synoptic Scale
gulf of Mexico
Mexican plateau

• The synoptic scale is the level just below the
  global scale.

medium spatial scale ("weather map" scale
) medium time scale Medium-range weather forecast
- flood control, combat drought
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Mesoscale
Land surfaces absorb and emit radiation more
efficiently than water surfaces. Therefore, a
thermally driven circulation will form. Sea
breeze may bring significant precipitation.
cold
warm
cold

• Mesoscale phenomena have an approximate size
  between 1km and 100 km and a time span between a
  few minutes to a day.

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Relation between different scales--Nested Grid

• Initial conditions
• Observed data
• or
• data from larger scale model

• A model may have a low grid resolution for a
  large area . Then, it has the ability to take a
  higher resolution grid and nest it over a region
  of importance.

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May it be from above to below?
imprecise model
The SST of the Atlantic Ocean will affect the
precipitation at Tokyo.
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Land surface model

• Although land(30) is smaller than ocean(70),
  over land, variations in soil moisture can lead
  to as large differences in BL ?e as several
  degrees in SST.

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The Worlds Water Cycle