Transcript Observing Climate Variability and Change Mr. T. Karl

Observing Climate
Variability and Change
Thomas R. Karl
National Oceanic and Atmospheric Administration
National Environmental Satellite Data and Information Service
National Climatic Data Center
Asheville, NC 28801-5001, USA
1) How has the
climate changed or
varied?
3) What are the causes
of climate change and
variability?
P
H
Y
S
I
C
A
L
P
R
O
C
E
S
S
2) How well do we
understand the climate
system ?
4) How can we characterize
the impacts of climate
change?
CLIMATE CHANGE
FORCINGS
$}
IMPACTS
$}
FOREST
MIGRATION
BIOLOGICAL
PROCESSES
C Y
R I
O E
P L
D
C
O
A
S
T
A
L
H
A
B
I
T
A
T
How significant are the uncertainties?
 State and Forcings Variables
 Few have quantitative confidence intervals (CIs) (including timedependent biases) e.g., global surface temperature, CO2
 Most CIs do not include
time-dependent biases
 For many, CIs are uncertain
or unknown
 Why?
 Adhering to climate observing
principles and guidelines still
does not have a high priority
Smoothed annual anomalies of global combined
land-surface air and sea surface temperatures (oC).
The Climate Observing System:
What is needed?
 Adoption of ten principles for climate monitoring
 More comprehensive global observations
--- Prioritization concept
 Improved global telecommunications
 Better use of data… more products
 Critical need for system
monitoring and oversight
responsibility --- Examples
The Climate Observing System:
What is needed?
Adherence to Ten Principles for both space- and
surface-based observations
1. Management of Network Change
6. Historical Significance
2. Parallel Testing
7. Complementary Data
3. Metadata
8. Climate Requirements
4. Data Quality and Continuity
9. Continuity of Purpose
5. Environmental Assessments
10. Data and Metadata Access
 The international framework for
sharing data is vital.
Definition of Terms
Impact – potential for reducing uncertainties
Time to Pay-Off – the time
required for an impact to be
realized, i.e., upgrading an
existing system or
implementing a new system
Feasibility – readiness to
implement the observing system
considering technical aspects and
resource requirements
Example: Demonstrating Prioritization Concept
A Global Network of
Reference Quality
Radiosonde Sites
Temperature Indicators “Climate Impacts”
Temperature Indicators “Climate Understanding”
Hydrological Indicators “Climate Impacts”
Hydrologic Indicators “Climate Understanding”
What are the causes of climate
change and variability
The Climate Observing System:
What is needed?
Observing Systems Oversight and
System Monitoring Capability
 Establish climate requirements for observing systems
(atmosphere, ocean, terrestrial, cryosphere), such as weather
services do today
 Includes instruments on satellites
 Spatial and temporal sampling, etc.
 Reprocessing and reanalysis
 Tracks the performance of the observations, the gathering of the
data, and the processing systems
 Resources and influence to fix problems
Real-time Network Performance Monitoring
U.S. Climate Reference Network
Observing and Data System Deficiencies
 Five different
research
teams using
independent
methods to
identify timedependent
biases in the
tropospheric
temperature
records
Teams:
NOAA – GFDL
– NCDC
Univ. of Alabama
UK Meteorological Office
Texas A & M University)
Percent of Teams Identifying Biases
Courtesy: Free et al
(in review BAMS)
The Climate Observing System:
What is needed?
 Adoption of ten principles for climate monitoring
 More comprehensive global observations
 Improved global telecommunications
 Better use of data… more products
 Critical need for system
monitoring and oversight
responsibility
Some Variables are Effectively Monitored for Trend
Scripps Institute of Oceanography
NOAA
Observing and Data System Deficiencies
 Impact of Satellite Orbital Drift
 Will be fixed on US NPOESS (2009)
Changes in orbits and equator crossing times of satellites are
aliased onto the diurnal cycle, requiring corrections
Ascending minus descending temperatures
MSU2 JJA 1989-91 from NOAA 11
MSU channel 2 temperatures over land, from Wentz (black lower)
and Christy-Spencer (red lower) and difference (top).
Diurnal corrections required for each
satellite.
Observing and Data System Deficiencies
Courtesy F. Wentz
 Effect of Calibration Target Correction on MSU Channel 2