Global, Regional, and Urban Climate Effects of Air Pollutants

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Global, Regional, and Urban Climate Effects of
Air Pollutants

• Mark Z. Jacobson
• Dept. of Civil Environmental Engineering
• Stanford University

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Modeled CO2(g) and Modeled v Measured Ocean pH
1751-2003
CO2(g) mixing ratio (ppmv)
Surface ocean pH
Data from Friedli et al. (1986) and Keeling and
Whorf (2003)
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Modeled Ocean Profiles 2004 2104 Under SRES A1B
Emission Scenario
Depth (m)
Depth (m)
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Effect of CO2(g) on Atmospheric Acids
Mixing ratio (ppbv)
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(No Transcript)
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Comparison of ff BC Climate Responses

• 1. Jacobson (JGR 107, D19, 2002). Size resolved
  (1 distribution) multi-component aerosols,
  size-resolved cloud formation on aerosols,
  size-resolved treatment of first and part of
  second indirect effects, climatological snow/ice
  albedo, emissions of Cooke et al. (1999), 2-D
  ocean module, many feedbacks.
• Fossil fuel BCOM 0.3 K (5-y average)
• 0.35 K (last year)
• Range of all simulations (0.15 to 0.5)
• 2. Ibid. (JGR 2004, in press). Same as (1) but
  treated first and second indirect effects,
  calculated snow/ice albedo, used early Bond et
  al. (2004) inventory.
• Fossil fuel biofuel BCOM 0.27 K (10-y avg.
  snow contrib. 0.06 K)
• 3. Ibid. Recent results. Same as (2) but used
  most recent Bond et al (2004) emission,, used two
  distributions (emitted ffbf BCOM and emitted
  other heterocoagulated BC) and 10 layers of
  energy diffusion to deep ocean.
• Fossil fuel biofuel BCOM 0.29 K (6-y avg.)

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Ten-Year-Avg. Globally-Averaged Temperature
Profile Differences
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Temperature Changes Due to Eliminating Emission
of Anthropogenic CO2, CH4, and f.f. BCOM
Cooling (K) after eliminating anthropogenic
emission
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Observed and Modeled Temp. Diff. w-w/o GHG and
Aerosols
(January only
Schneider and Held (2001)
Latitude (degrees)
(4 y an. avg.)
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Modeled (4 y avg.) Temp. Diff. w-w/o Anth. GHG
alone
Latitude (degrees)
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Modeled (4 y avg.) and Radiosonde Vertical Temp.
(K) dif. w-w/o GHG and Aerosols
300-100 mb 9-16 km 100-30 mb 16-24 km
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Feb. Aug. California Column BC Dif. w-w/o Anth.
Aer.
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Column POM Dif. w-w/o Anth. Aer.
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Column SOM Dif. w-w/o Anth. Aer.
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Column S(VI) Dif. w-w/o Anth. Aer.
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Column NO3- Dif. w-w/o Anth. Aer.
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Column NH4 Dif. w-w/o Anth. Aer.
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Column Aerosol LWC Dif. w-w/o Anth.Aer.
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Column Total Aerosol Dif. w-w/o Anth. Aer.
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Aerosol 550 nm Optical Depth Dif. w-w/o Anth.Aer.
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Cloud 550 nm Optical Depth Dif. w-w/o Anth.Aer.
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Cloud 550 nm Scattering Optical Depth Profile Dif.
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Down-Up Surface Solar Radiation Dif. w-w/o
Anth.Aer.
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Down-Up Surface Thermal-IR Radiation Dif. w-w/o
Anth.Aer.
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Irradiance Profile Dif. Over California
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Near-surface Temperature Dif. w-w/o Anth.Aer.
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Zonal Temp. Profile Dif. w-w/o Anth.Aer.
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Temperature Profile Dif. Over California
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Near-surface RH Dif. w-w/o Anth.Aer.
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Zonal RH Dif. w-w/o Anth.Aer.
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Cloud LWC Dif. w-w/o Anth.Aer.
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Cloud Liquid and Ice Profile Dif. Over California
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Modeled vs. Measured Feb. 1999 Precipitation
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Modeled Feb. 1999 vs. Measured Feb. Clim. Prec.
Data courtesy of Guido Franco
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Precipitation Dif. w-w/o Anth.Aer.
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Baseline BC in precipitation
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SCAB Column Total Aerosol Dif. w-w/o Anth.Aer.
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SCAB Aerosol Optical Depth Dif. w-w/o Anth.Aer.
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SCAB Cloud Optical Depth Dif. w-w/o Anth.Aer.
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Cloud 550 nm Scattering Optical Depth Profile Dif.
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SCAB Down-Up Surface Solar Radiation Dif. w-w/o
Anth.Aer.
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SCAB Downward UV Radiation Dif. w-w/o Anth.Aer.
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SCAB Near-Surface OH Dif. w-w/o Anth.Aer.
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SCAB Down-Up Surface Thermal-IR Radiation Dif.
w-w/o Anth.Aer.
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Irradiance Profile Dif. Over SCAB
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SCAB Near-Surface Temperature Dif. w-w/o Anth.Aer.
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Temperature Profile Dif. Over SCAB
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SCAB Baseline Precipitation
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SCAB Precipitation Dif. w-w/o Anth.Aer.
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Summary

• Globally-averaged surface ocean pH may have
  decreased from about 8.25 to 8.14 from 1751 to
  2004 Under the SREAS A1B emission scenario, pH
  may decrease to 7.85 in 2100, for an increase in
  the hydrogen ion by a factor of 2.5 since 1751.
  Ocean acidification may increase concentrations
  of atmospheric acids and decrease those of bases,
  although the magnitude is uncertain.
• Three global simulation results suggest a warming
  due to ffbf BC of 0.25 to 0.3 K in the 5- to
  10-year average with a range of 0.15 K to 0.5 K
• Maximum warming and cooling due to anthropogenic
  GHGs and aerosols exceed those of GHGs alone.
  Aerosols act on top of GHGs to enhance extreme
  warm and cool climate conditions.
• Modeled aerosol particles and gas-phase
  precursors appear to decrease precipitation in
  mountainous regions and increase it beyond the
  mountains, cool surface-air temperatures,
  slightly increase atmospheric temperatures,
  reduce solar and UV radiation and OH, and
  increase thermal-IR radiation to the surface in
  California.