Phenology

1
Phenology

• Changes in
• North American spring
• as indicated by
• the lilac phenology network

2
Research Contributions

• Phenology analyses from D. Wolfe
• Phenology data from J. Caprio
• Climate data from USA National Climatic Data
  Center
• NSF Grants ATM-9510342, 9809460, and 0085224

3
Research Contributions

• Delayed Moving Average (DMA) Satellite start of
  season (SOS) technique developed by Bradley Reed
  and colleagues
• Seasonal Midpoint NDVI (SMN) Satellite start of
  season (SOS) technique developed by Michael White
  and colleagues

4
Terrestrial Biosphere Dynamic Change Detection

• Satellite Phenology
• Cloned Species Phenology
• Native Species Phenology
• Simulated Phenology (Models)

5
Satellite Phenology

• Advantages
  1) Global coverage
  2) Integrated signal
• Limitations
  1) Short period-of-record
  2) Cloud cover interference
  3) Interpretation issues
  4) Small set of measures

6
DMA NDVI Start of Season 1995(Reed et al., mean
day 74, March 15th)
7
SMN NDVI Start of Season 1995 (White et al.,
mean day 124, May 4th)
8
Cloned Species Phenology

• Advantages
  1) Ideal for model development
  2) Standardized response to
  environment 3) Broad range
• Limitations
  1) Lack of network geographical coverage
  2) Not adapted to local
  environment

9
Lilac First Leaf
10
Lilac First Leaf 1961-2000 Slope
11
Lilac First Leaf 1961-2000 Slope
12
Lilac First Leaf NE USA
13
Lilac First Leaf NE USA
14
Lilac First Bloom
15
Lilac First Bloom 1961-2000 Slope
16
Lilac First Bloom 1961-2000 Slope
17
Lilac First Bloom NE USA
18
Lilac First Bloom NE USA
19
Native Species Phenology

• Advantages
  1) Adapted to the local environment
  2) Precise signal
• Limitations
  1) Lack of network geographical coverage
  2) Limited range
  3) Geographical
  variations in response

20
Simulated Phenology

• Advantages
  1) Broad coverage if using simple input
  2) Standardized
  response
• Limitations
  1) Model inadequacies
  2) Small set of events and plants

21
Spring Indices Suite of Measures

• First frost date in Autumn
• Composite chill date (SI models)
• First leaf date (SI models)
• First bloom date (SI models)
• Last frost date in Spring
• Frost period
• Damage index value (first leaf last frost)
• Average annual and twelve average monthly
  temperatures

22
First 2.2C Freeze Date 1961-2000 Slope
23
October Average Temperature 1961-2000 Slope
24
SI Chill 1961-2000 Slope
25
SI First Leaf Departures in North America
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SI First Leaf 1961-2000 Slope
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SI First Bloom 1961-2000 Slope
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Last Freeze Date Departures in North America
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Last 2.2C Freeze Date 1961-2000 Slope
30
Integrated ApproachExample WisconsinZhao and
Schwartz (2003)

• Satellite phenology (DMA SOS)
• Simulated phenology (SI
  first bloom dates)
• Native species phenology (WPS records of first
  bloom date for 21 introduced and 32 native
  species)

31
Integrated Species Indices (ISI)southwestern
Wisconsin
32
Critical Data/Analysis Needs

• Interpretation/Comparison of satellite phenology
• National, continental, and global scale phenology
  networks
• Interpretation of ripple effects in biomes

33
Global Assessment

• North America
• China and East Asia
• former Soviet Union
• Europe
• Australia
• South America