Upload
marilynn-willis
View
223
Download
0
Embed Size (px)
DESCRIPTION
1979 – 2010 daily data available for over 100 variables across the circumpolar north
Citation preview
CARMA’s Climate databaseJ. Fox
L. Witter S. Thorisson
Why a CARMA climate database
• CARMA’s goal to monitor and assess impacts of global change on caribou
• Major approach is cross-herd comparisons• Need to compare (how are herd habitats similar)
and contrast (how are herd habitats different)• Climate plays a central role in controlling caribou
abundance and distribution• Ideal to have one source for the data – climate
data
1979 – 2010 daily data available for over 100 variables across the circumpolar north
…a few words about MERRA data
• Universal coverage for over the last 30 years• Brings together all climate data within the satellite era• Ensures that different satellite provide a consistent
measure of the environment• Data at least daily and, for example temperature, every 3
hours• 72 variables offered• Grid size ½ degree latitude by 2/3 degree longitude• Data is available to download within months• Estimate for CARMA to provide annual updates is ~ 18
hours – of which 15 hours is for MERRA data download
STEP 1. DEFINE SEASONAL RANGES
8 polygons per herd
for example – Bluenose West Herd
calving
summer
springwinter
fall
taiga
tundra
whole herd
calving summer
fall
2 types of tables created
calving summer
fall
Seasonal range tables Caribou movement tables
winter winter
104 grids PCH winter219 grids Taimyr winter
Caribou-relevant climate derivatives
winter
spring/calving
summer autumn
autumn
…a few examples:comparing years for a herd
(summer temperature)
…a few examples:comparing herds (summer
temperature)
…a few examples:snow depth comparing herds
…a few examples:snow depth comparing years
…a few examples:snow depth comparing years
…a few examples:some caribou-specific variables
How much data?
• MERRA raw data 21.5 Gbytes• Polygon focused tables 2.1 Gbytes• Caribou focused tables 138 Mbytes
• TOTAL ~ 25 GBytes
Some questions for the breakout
• Data quality?– Greenness Index, Leaf Area Index– validation
• Documentation needs?• Access?• Additional caribou related variables?• Are there basic summaries needed?• Trend analysis?• Tele-connections?• Update schedule – annual, timing?