Dennis&Baldocchi& Professor&of&Biometeorology& University...
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Overview of Climate Change Issues: Trends and Implica:ons on Agriculture, Ecology, and Physiology Dennis Baldocchi Professor of Biometeorology University of California, Berkeley
Transcript of Dennis&Baldocchi& Professor&of&Biometeorology& University...
Overview of Climate Change Issues: Trends and Implica:ons on Agriculture, Ecology,
and Physiology
Dennis Baldocchi Professor of Biometeorology
University of California, Berkeley
Outline
• Overview of Current and Future Trends in Climate
• ImplicaAons on Agriculture • Experiences from Our Research on Climate, Ag and Rangelands
Mauna Loa: UC Scripps & NOAA CMDL; CDIAC
year
1960 1970 1980 1990 2000 2010
CO
2 (pp
m)
300
320
340
360
380
400
Fact 1: CO2 IS INCREASING
Fact 2. CO2 Concentra:ons are the Highest in a Million Years
ESPM 111 Ecosystem Ecology
hIp://www.climatechange2013.org/images/figures/WGI_AR5_Fig2-‐14.jpg
Global Temperature Change, IPCC 2014 Report
Fact 3. Various Independent Data Sets show Global Temperature are Rising
hIp://data.globalchange.gov/assets/be/54/32981ede2704c6526759a9cae371/CS_global_temperature_Ame_series_v5.png
Modesto
Year
1920 1940 1960 1980 2000 2020
Mea
n A
nnua
l Air
Tem
pera
ture
, C
14
15
16
17
18
19
Temperature Trends in the Central Valley
hIp://nca2014.globalchange.gov/sites/report/files/images/web-‐large/ten-‐indicators-‐hi.jpg
Warming Is Consistent with Many Other Changes Being Observed
hIp://data.globalchange.gov/assets/d6/f6/5a96b397d37268ef8a22ffd473a7/CS_average_annual_temp_global_V7.png
hIp://data.globalchange.gov/assets/d0/a9/ee48a3804ae77da52a267a6ccebb/SW_temperature_projecAons_14346_v6.png
Camp Pardee
Year
1940 1950 1960 1970 1980 1990 2000 2010
annu
al P
reci
p (m
m)
0
200
400
600
800
1000
1200
mean: 548.6446stddev: 196.2281
Interannual VariaAon in PrecipitaAon is Great, and Exceeds Trends in Near Term
hIp://data.globalchange.gov/assets/07/36/88662b9d9454dd72cf354a939e7c/CS_seasonal_precip_projecAons_RCP-‐NO_TITLE_V8.png
Precipita:on Projec:ons
hIp://nca2014.globalchange.gov/sites/report/files/images/web-‐large/Figure-‐20.2-‐hi.jpg
What Are the ImplicaAons on California Agriculture and Rangelands?
Point Reyes StaAon, Jan 2014
Impacts of Climate Change
• Elevated CO2 – Greater Rates of Photosynthesis
• More Growth • More Water Use
– Stomatal Closure • BeIer Water Use Efficiency
• Warmer Temperature – Longer and Earlier Growing Season
• Increase Frost Risk, Less Winter Chill AccumulaAon – More Water Use and Drought Stress – More RespiraAon
• Rainfall – More Droughts and Fires – Less Snow Fall, Earlier Snow Run Off, Less Storage as Snow Pack
hIp://nca2014.globalchange.gov/sites/report/files/images/web-‐large/SW_frost-‐free-‐season_12449_V5_0.png
hIp://nca2014.globalchange.gov/highlights/report-‐findings/agriculture
Change in Frost Free Season
Warming Affects Phenology, the Timing of Bud Break and Leaf Out
Orland, Ca
Year
1940 1950 1960 1970 1980 1990 2000 2010
Chi
ll H
ours
, bel
ow 7
.22
o C
400
600
800
1000
1200
1400
1600
1800
Coefficients:b[0] 14228b[1] -6.711r ≤ 0.234
Year
1940 1950 1960 1970 1980 1990 2000 2010
Chi
ll D
egre
e-H
ours
, bel
ow 7
.22
o C
0
1000
2000
3000
4000
5000
Coefficients:b[0]: 47974b[1]: -23.01r ≤: 0.248
Downward Trend in Chill Hours near Orland, northern Sac Valley
50+ year Record, Coop Data
Baldocchi and Wong, ClimaAc Change, 2008
‘But a'er a winter that lacked much of the rain and fog needed to keep temperatures down, cherry crops around the state are lighter’, said Len Del Chiaro, who operates two U-‐pick cherry businesses in the area. San Jose Mercury May 18, 2014
hIp://data.globalchange.gov/assets/3e/b5/9ada65bb3cc8b5dd0f67d6aa7230/AG_chill_hours_12518_v7.png
Winter Chill Models
Darbyshire et al 2011. AgForMet
Iconic Fog Picture of the Central Valley
Winter Fog in the Central Valley Promotes Chill AccumulaAon
Valley ‘Old-‐Timers’ say Tule Fog isn’t as Severe as it Used to Be
Central Valley, AVHRR
Year
1980 1985 1990 1995 2000 2005 2010 2015
Frac
tion
of F
og D
ays,
Nov
-Feb
0.0
0.1
0.2
0.3
0.4
0.5
AVHRR MODIS
Winter Tule Fog is Declining, On average by 46% from 1981-‐2014
38 days
20 days
AVHRR 1981-‐2000 MODIS, 2001-‐2012
Fog Frac:on in the Central Valley, November-‐February
Fresno
Year
1900 1920 1940 1960 1980 2000 2020
Num
ber o
f Fog
Day
s pe
r Wni
ter
0
10
20
30
40
50
60
70
ObservationsSatellite
Declining Trends in Fog Maybe a Recent Phenomenon
Combined Roles on Reduced Ag Burning, Air PolluAon and Warmer Winters
hIp://nca2014.globalchange.gov/highlights/report-‐findings/agriculture
Yield Declines
hIp://nca2014.globalchange.gov/sites/report/files/images/web-‐large/AG_crop-‐yields_12356_v5.png
Key Message 1: Increasing Impacts on Agriculture Climate disrupAons to agricultural producAon have increased in the past 40 years and are projected to increase over the next 25 years. By mid-‐century and beyond, these impacts will be increasingly negaAve on most crops and livestock.
Key Message 2: Weeds, Diseases, and Pests Many agricultural regions will experience declines in crop and livestock producAon from increased stress due to weeds, diseases, insect pests, and other climate change induced stresses.
hIp://nca2014.globalchange.gov/sites/report/
Key Message 3: Extreme PrecipitaAon and Soil Erosion Current loss and degradaAon of criAcal agricultural soil and water assets due to increasing extremes in precipitaAon will conAnue to challenge both rainfed and irrigated agriculture unless innovaAve conservaAon methods are implemented.
Key Message 4: Heat and Drought Damage The rising incidence of weather extremes will have increasingly negaAve impacts on crop and livestock producAvity because criAcal thresholds are already being exceeded.
hIp://nca2014.globalchange.gov/sites/report/
Climate Change and Ecosystems and Ag
• California is a Great Natural Laboratory for Studying Environmental Change due to its Strong Climate Gradients and Interannual Variability
DeIo et al
Interannual VariaAon in Net Carbon Exchange of Annual Grasslands (red) and Oak Savanna (blue)
