Metadata Supplement - Climate, Reference Precipitation and Sunshine Data Notes

1. Climate Observations

Time of Observations: 0800 and 1600 local time

Equipment:

•	Temperature 
Maximum and minimum thermometer in Stevenson screen.  Reset temperature is read from the minimum thermometer after being reset.

•	Precipitation 
Rain - Type B Standard rain gauge
Snow - NIPHER shielded snow gauge.
			Snow Board

•	Rain, snow and water equivalent >= 0.2 mm are recorded to the nearest 0.1 mm. Measurements <0.2 are recorded as trace (T). Refer to the Manual of Climatological Observations, Chapter 3.4.4.
•	Snowfall measured at 8am and 4pm is that snow which occurred since the last observation and is the measurement taken from the snow board. Snow board is cleaned after the measurement has been recorded ensuring that the snow cleared is distributed around the area so as to not create a drift.  Snow board is re-located if drifts form around it.
•	Depth of the snow on ground is recorded to the nearest whole centimeter during the AM observation only. This is the accumulated depth of all snow. Trace (T) is entered for snowfall < 0.5 centimeters. A number of measurements are taken in open areas around the climate instrument area with the average being recorded. Refer to the Manual of Climatological Observations chapter 3.9.1
•	Remarks are a summary of the weather conditions that have occurred since the last observation. 
•	Dew  - measurements are recorded on the climate station report in the remarks column with a note that the measurement is dew (eg: Dew 0.1mm).  
•	Visibility - is the visibility at the time of the observation.
•	Precipitation begin and end times - This is the time the precipitation began and ended each calendar day.

2.  Reference Precipitation

Time of Observations: 0800 and 1600 local time

Collectors:
Type B Standard rain gauge
NIPHER Snow gauge 
Pit gauge
Copper gauge
DFIR gauge

All measurements are water equivalent. DFIR is measurement 365 days per year.  Rain gauges deployed when temperatures are above freezing ( April to November ), NIPHER snow gauge for below freezing measurements (November to April).  Collectors may be deployed outside these timeframes at the observers discretion is weather conditions warrant.

•	Dew - The measurement is recorded on the reference gauge log under the appropriate heading. A measured amount of 0.1 is to be recorded if that is an accurate measurement. If not measurable then T is entered for trace. Dew is recorded under the PCPN Type, Intensity column.

Types of Precipitation and Symbols and Intensity

Rain 						-RA, RA, +RA
Rain Showers				-SHRA, SHRA, +SHRA
Drizzle					-DZ, DZ, +DZ
Freezing Rain				-FZRA, FZRA, +FZRA
Freezing Drizzle				-FZDZ, FZDZ, +FZDZ
Snow						-SN, SN, +SN
Snow Grains				-SG, SG, +SG
Ice Crystals				 IC
Ice Pellets					-PL, PL, +PL
Ice Pellet Showers			-SHPL, SHPL, +SHPL 
Snow Showers				-SHSN, SHSN, +SHSN
Snow Pellets				-GS, GS, +GS
Hail						-GR, GR, +GR
 
Intensity of Precipitation

Light – (eg. -SHRA)
Moderate (SHRA)
Heavy + (+SHRA)

Very Light - (--shra) this intensity is no longer used

Definitions:

Drizzle – fairly uniform precipitation, composed exclusively of fine drops of water. The drops appear to almost float in the air. Drizzle falls from fairly continuous and dense layers of stratus sometimes touching the ground as fog.
Rain – precipitation of liquid particles. These are normally larger than drops of drizzle but may occasionally appear as drizzle owing to partial evaporation if dropping near the edge of a rain zone.
Freezing Drizzle and Freezing Rain – drizzle or rain which freezes on impact with the ground or other objects near the earth’s surface. 
Snow – precipitation of mainly hexagonal ice crystals, most of which are branched or star shaped and are generally clustered together to form snow flakes.
Snow Pellets – precipitation of white and opaque particles of ice. They are either spherical or conical and are brittle and easily crushed. When they fall on hard ground, they bounce and often break up. Snow pellets always occur in showers and are often accompanied by snow flakes or rain drops when the temperature is around 0^o C.
Snow Grains – precipitation of very small white and opaque grains of ice. These grains are fairly flat or elongated and their diameter is generally less than 1 mm. When the grains hit hard ground they do not bounce or shatter. They usually fall in small quantities from stratus or fog, and never in the form of a shower. Looks like table salt.
Ice Pellets – Precipitation of transparent or translucent pellets of ice which are spherical or irregular having a diameter of 5 mm or less.
Hail – precipitation of small balls or pieces of ice (hailstones) with a diameter ranging from 5 to 50 mm or more. Hail is generally observed during heavy thunderstorms. They always fall as showers.
Ice Crystals – needles, columns or plates of ice, often so tiny they appear suspended in the air. They fall from cloud or cloudless sky and only at very low temperatures.

Abbreviations - Obstructions to Vision 

Fog						FG (vsby <1km)
Mist						BR (vsby >=1km)
Ice Fog					IF
Haze						HZ
Smoke					FU
Blowing Snow				BLSN
Blowing Sand				BLSA
Blowing Dust				BLDU					

Character of Precipitation

Showers – precipitation falling from cumuliform cloud and often (but not always) begins and ends abruptly. Showers usually occur in periods of short duration, perhaps 15 minutes or so, but they may last longer. Usually there are rapid fluctuations in the intensity.

Continuous – precipitation that occurs for at least 1 hour without a break and does not have the characteristics of showers. 

Intermittent – precipitation which does not have the characteristics of showers but has stopped and recommenced at least once during the hour. 

Intensity by Visibility Criteria

Snow, Snow Shower, Snow Grains, Snow pellets, Drizzle, Freezing Drizzle :

Light  if visibility is 1 km (5/8 mile) or more

Moderate  if alone (no other precipitation and/or obstruction to vision is present) and the visibility is reduced to <1km to 0.6km (<5/8 to 3/8 mile).

Heavy if alone (no other precipitation and/or obstruction to vision is present) and the visibility is reduced to <0.6km (<3/8 mile) or less).

Intensity by Rate of Fall Criteria

Rain, Rain Showers, Freezing Rain:

Light if rate of fall is 2.5 mm per hour or less

Moderate if rate of fall is 2.6 mm to 7.5 mm per hour

Heavy if rate of fall is 7.6 mm per hour or more

Other Measurement Criteria

Ice Pellets, Hail:

Light – few stones or pellets, slow accumulation on the ground.

Moderate – rapid accumulation on the ground

Heavy – very rapid accumulation on the ground

Drizzle, Freezing Drizzle:

Light – less than 0.2 mm per hour accumulation

Moderate – 0.2 to 04 mm per hour accumulation

Heavy – 0.5 or more per hour accumulation.

Precipitation Reference Gauge Log

The following abbreviations are used for the reference precipitation log when there is no measurable precipitation.

0 - No precipitation
T - Precipitation not measurable
M - Missing Data (could be operator error or data not available due to  other reason i.e. snow in rain gauge but not measurable). Remarks column is used to record the reason.
N - Collector not in service

Sunshine	

Time of Observations: 0800 and 1600 local time

Equipment:  Campbell Stokes Sunshine Recorder

Bright sunshine is recorded in tenths of an hour. "Bright" sunshine is characterized by sunshine bright enough to burn or scorch a standard card.  Reference: Department of Transport Meteorological Branch Sunshine 1970.