DAVIS Vantage Pro2 manual EvapoTranspiration ET, Iii

Weather Data Measured & Calculated

Skin Phototype (EPA)

1

2

Some Burn

3

4

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I

	UV Dose that Causes Sunburn
						II	Canada)
		All Burn				IV
							(Environment
						III	Skin Type
						V
						VI
40	60		80	100	120 mJ/cm2

1	2	3	4	5	6
		UV Dose (MEDs)

Weather Envoy can also display UV Index, an intensity measurement first defined by Environment Canada and since been adopted by the World Meteo- rological Organization. UV Index assigns a number between 0 and 16 to the current UV intensity. The US EPA categorizes the Index values as shown below. The lower the number, the lower the danger of sunburn. The Index value published by the U.S. National Weather Service is a forecast of the next day’s noontime UV intensity. The Index value displayed by the Weather Envoy is the result of a real-time measurement.

Table A3: UV Index and Exposure Category

		Index Values	Exposure Category
		0 - 2	Minimal
		3 - 4	Low
		5 - 6	Moderate
		7 - 9	High
		10+	Very High
	EvapoTranspiration (ET)
Note:	Requires optional solar radiation sensor (#6450, included on Vantage Pro or Vantage
	Pro2 Plus weather stations).

EvapoTranspiration (ET) is a measurement of the amount of water vapor returned to the air in a given area. It combines the amount of water vapor

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