Forecasting Climate and Ozone
Changes on Multi Decadal Time Scales
Judith Lean
Space Science Division, Naval Research Laboratory, Washington DC
Sources of Global Change
- climate, atmosphere, ozone
Data-driven Models of Global Change
-climate, atmosphere, ozone
Future Scenarios
- natural and anthropogenic
- new Maunder Minimum impact?
SORCE STM Sedona 16Sep2011
There are Many Causes of Climate, Atmosphere
and Ozone Change
Natural Forcings
• solar variability - direct and indirect effects
• volcanic eruptions - stratospheric aerosols
Internal Oscillations
El Nino
• atmosphere-ocean couplings
- El Niño Southern Oscillation (ENSO)
- North Atlantic Oscillation (NAO) La Niňa
- Quasi biennial Oscillation (QBO)
Anthropogenic Forcings
• atmospheric GH gases - CO2, CH4, CFCs, O3, N2O
• tropospheric aerosols - direct and indirect effects
of soot, sulfate, carbon, biomass burning, soil dust
• land cover changes
Natural and Anthropogenic Climate
Influences in the Space Era
El Nino
La Nina
optical thickness at 550 nm compiled by Sato et al. (1993) since
1850, updated from to 1999 from
giss.nasa.gov and extended to the
present with zero values
bright faculae
El Chichon
Pinatubo
multivariate ENSO index
- weighted average of the main ENSO
features contained in sea-level pressure,
surface wind, surface sea and air
temperature, and cloudiness in the
tropical Pacific (Walter and Timlin, 1998)
net effect of eight different components
Hansen et al. (2007)
dark sunspots
Net effect of sunspot darkening and facular brightening
- model developed from observations of total solar
irradiance (Lean et al. 2005)
Global Surface Temperature Response to
Natural and Anthropogenic Influences: 1980(Lean
2008
(Kopp and Rind,
Lean,GRL,
GRL,2009)
2011)
Temperature Anomaly (K)
… CRU temperature data, Univ. East Anglia, UK
NRL’s General Linear Model:
ENSO + volcanic aerosols +
solar activity + anthropogenic
effects explain 85%
76% of
observed temperature variance
(3 lags)
(2 lags)
+0.2oC 1997-98 “super” ENSO
-0.3oC Pinatubo Volcano
+0.1oC Solar cycle 23
+0.4oC Anthropogenic effects
1980-2006
Annual Surface Temperature Regional
Response Patterns (5o×5o lat-long)
no observations
Lean & Rind, GRL, 2008, 2009
Lean, WIRE, 2010
Kopp & Lean, GRL, 2011
Natural and
Anthropogenic
Influences on
Earth’s
Atmosphere
2 km
LOWER
TROPOSPHERE
5 km
MIDDLE
TROPOSPHERE
19 km
LOWER
STRATOSPHERE
19 km
5 km
2 km
Lean, WIRE, 2010
solar increase  warming
CO2 increase warming
Volcanoes  cooling
solar increase warming
CO2 & CFC increase  cooling
Volcanoes  warming
Temperature and Ozone Global Climatology
Regression Model Analysis:
Volcano:
ΔT = +1.5oC ΔO3 = -3 DU
Solar cycle:
ΔT = +0.3oC ΔO3 = +6 DU
Long-term Trend: (1980 - 2010)
ΔT = -0.7oC ΔO3 = -5 DU
In contrast:
Thompson & Solomon, 2009
“The long-term, global-mean
cooling of the lower
stratosphere stems from two
downward steps in temperature,
both of which are coincident
with the cessation of transient
warming after the volcanic
eruptions of El Chichón and
Mount Pinatubo“
Ozone
Temperature
Temperature and Ozone Regional Responses
Solar-Terrestrial Processes Depend on
Wavelength, Geography, Altitude
UV radiation
(λ < 315 nm)
Sun
20 Wm-2
unit
optical
depth
near UV,VIS,IR
Radiation
(λ > 315 nm)
1341 Wm-2
Stratosphere
cloud cover
ozone
Climate Modeling Capability: Adequate?
derived from
observations
simulated by
GISS Model E
climate model
IPCC AR5 climate
change
simulations now
underway input
solar spectral
irradiance
(AR4 used TSI)
Schmidt et al., 2011
“Climate Forcing
Reconstructions for
use in PMIP
simulations in the
last millennium”
.. ..inputs are based
on NRL SSI solar
spectral irradiance
variability model
Improved Surface Temperature Prediction for
the Coming Decade from a Global Climate
Model
Smith et al., Science, 2007
… climate will continue to warm, with at least
half of the years after 2009 predicted to
exceed the warmest year currently on
record…..ΔT=0.3oC from 2004-2014
Advancing decadal-scale climate prediction in
the North Atlantic sector
Keenlyside et al., Nature, 2008
….global surface temperature may not
increase over the next decade, as natural
climate variations in the North Atlantic and
tropical Pacific temporarily offset the
projected anthropogenic warming.
How – and Why - will Climate Change
in the next few Decades?
Assuming Past is Prologue…. future near-term climate change will vary
(Lean and Rind, GRL, 2009)
Temperature Anomaly (K)
because of both natural and anthropogenic influences
There will be both warming
and cooling in the next few
decades
cycle 23
Future Solar
Irradiance?
How active will solar
cycle 24 be?
cycle 24
SORCE
JPSS
- 40% higher than cycle 23
(Dikpati et al, 2005)
- less active than cycle 23
Sunspot number
Are we entering a protracted
solar minimum? (NO.. not yet )
cycle
14
cycle
20
Foster, 2004
Foster, 2004
Lean, 2000
Shapiro et al. 2011
Krivova et al. 2007
Tapping et al. 2007
Wang, Lean, Sheeley, 2005
Solanki, Krivova, 2005
Fligge, Solanki, 2000
Lean, Beer, Bradley, 1995
Hoyt, Schatten, 1993
Lean, Skumanich, White, 1992
Lean, Skumanich, White, 1992
Schatten, Orosz, 1990
Pending Maunder Minimum?
Speculated Total Solar Irradiance Reduction
Relative to Contemporary Minimum
11-year cycle only, no background component
solar
cycle
increase
Temperature Anomaly (K)
Maunder Minimum Influence on Climate
in the next few Decades
If TSI decrease from 2020 to
2030 is:
1X solar cycle  T=-0.1oC
2X solar cycle  T=-0.2oC
5X solar cycle  T=-0.5oC
Note: An actual Maunder Minimum
may take >100 years – not 10 years
– to eventuate.
Conclusion: A new
Maunder Minimum will
NOT cause another
Little Ice Age
Is a big El Niño
coming?
EL NIÑO/SOUTHERN OSCILLATION (ENSO)
DIAGNOSTIC DISCUSSION
issued by
CLIMATE PREDICTION CENTER/NCEP/NWS
5 November 2009
- cycle 21 & 22
was
10.6
ENSOlength
Alert System Status:
El Niño
Advisoryyears
- cycle 23 length is >12 years
- there were no sunspots from Jan to
Sept 2008
- some solar and geomagnetic indices
are historically (over decades) low
Synopsis: El Niño is expected to continue strengthening and last through at least the Northern
Hemisphere winter 2009-2010.
During October 2009, sea surface temperature (SST) anomalies increased across the central and
eastern equatorial Pacific Ocean (Figs. 1 & 2). The Niño-3.4 index increased nearly a degree with the
most recent weekly value at +1.5°C (Fig. 2). Above-average subsurface temperature anomalies increased
across a large region of the central and east-central Pacific, with anomalies ranging between +1 to +5°C
by the end of the month (Fig. 3). Consistent with this warming, subsurface oceanic heat content
anomalies (average departures in the upper 300m of the ocean, Fig. 4) also increased during the month.
In addition, low-level westerly and upper-level easterly wind anomalies strengthened over much of the
equatorial Pacific. The pattern of tropical convection also remained consistent with El Niño, with
enhanced convection over the west-central Pacific and suppressed convection over Indonesia.
Collectively, these oceanic and atmospheric anomalies reflect a strengthening El Niño.
There continues to be disagreement among the models on the eventual strength of El Niño, but
the majority indicate that the three-month average Niño-3.4 SST index value will range between +1.0°C
and +1.5°C during the Northern Hemisphere winter (Fig. 5). Consistent with the historical evolution of
El Niño, a peak in SST anomalies is expected sometime during November-January. At this time, there is
a high degree of uncertainty over how long this event will persist. Most of the models suggest that this
event will last through March-May 2010, although the most likely outcome is that El Niño will peak at
least at moderate strength (3-month Niño-3.4 SST index of +1.0°C or greater) and last through at least the
Northern Hemisphere winter 2009-10.
- polar fields
have reversed
-there have been
similar long quiet
episodes in the
past El Niño/La Niña Current
- recent newncep.list.ensocycle activity
Expected El Niño impacts during November 2009-January 2010 include enhanced precipitation
over the central tropical Pacific Ocean and a continuation of drier-than-average conditions over Indonesia.
For the contiguous United States, potential impacts include above-average precipitation for Florida,
central and eastern Texas, and California, with below-average precipitation for parts of the Pacific
Northwest. Above-average temperatures and below-average snowfall is most likely for the Northern
Rockies, Northern Plains, and Upper Midwest, while below-average temperatures are expected for the
southeastern states.
This discussion is a consolidated effort of the National Oceanic and Atmospheric Administration
(NOAA), NOAA’s National Weather Service, and their funded institutions. Oceanic and atmospheric
conditions are updated weekly on the Climate Prediction Center web site (
Conditions and Expert Discussions). Forecasts for the evolution of El Niño/La Niña are updated
monthly in the Forecast Forum section of CPC's Climate Diagnostics Bulletin. The next ENSO
Diagnostics Discussion is scheduled for 10 December 2009. To receive an e-mail notification when the
monthly ENSO Diagnostic Discussions are released, please send an e-mail message to:
update@noaa.gov .
Climate Prediction Center
National Centers for Environmental Prediction
NOAA/National Weather Service
Camp Springs, MD 20746-4304
Near-Term El Niño Forecasting
…but El Niño persistence may
permit some forecasting skill
once event has commenced
Figure 5. Forecasts of sea surface temperature (SST) anomalies for the Niño 3.4 region (5°N-5°S, 120°W170°W). Figure courtesy of the International Research Institute (IRI) for Climate and Society.
Figure updated 15 October 2009.
“..no firm projection about about the
future behavior of El Niño variability
can be made because the (IPCC
2007/CMIP3) models disagree”
Coelho & Goddard, J. Clim., 2009
Projected Changes in the Lower Stratosphere
Temperature at 19 km
(preliminary)
Total Ozone
Total column ozone will likely return to 1980 levels between 2025 and 2040, well before
the return of stratospheric halogens to 1980 levels between 2045 and 2060…. CCM’s
suggest this early return is primarily a result of GHG-induced cooling of the upper
Forecast:
from…
to…
Forecasting Climate and Ozone
Changes on Multi Decadal Time Scales
SUMMARY
Natural influences, including solar irradiance variations, have altered
Earth’s surface temperature, atmosphere and ozone in the recent
past; these influences will continue to be detectable in future
decades, superimposed on anthropogenic trends.
Natural influences and anthropogenic influences have different
relative strengths in the stratosphere relative to the surface
- solar influence increases 3X
- anthropogenic and volcanic influences change sign
Lower stratospheric climatology results from solar, oscillatory and
anthropogenic influences, in addition to (not just from) volcanic activity
Surface temperatures will continue to increase
Lower stratospheric temperature will remain at current levels
Total ozone will increase, exceeding 1980 levels as soon as 2025
Relative Climate
Forcing of Solar
Irradiance, ENSO
and Aerosols
r=0.916
r=0.912
“The new study (Kaufmann et al.,
PNAS, 2011) shows that while
greenhouse gas emissions continued
to rise, their warming effect on the
climate was offset by the cooling
produced by the rise in sulphur
pollution.”
http://environmentalresearchweb.org/
ΔF=0.24 Wm-2
Did China’s coal burning
REALLY offset global
warming in the past decade?
(No)
ΔF=0.13 Wm-2
Atmospheric Temperature Regional Responses
lower troposphere
2 km
middle troposphere
5 km
lower stratosphere
19 km
Solar Spectral Irradiance Measurements
individual
measurements
are offset-adjusted
72%
2%
NRLSSI
model of faculae
and sunspot
influences
0.15%