Overview of Climate Science GHG Analysis Methods and Resources

Overview of Climate ScienceGHG Analysis Methods and Resources
Jeff Houk, FHWA Resource Center
Ohio Climate Change and Transportation Planning Workshop
July 19, 2011

2
Greenhouse gases absorb radiation from the sun, warming the atmosphere. The physics of this are very well understood and easily measured.
Rising concentrations of greenhouse gases from human activities are causing warming beyond current conditions
Source: USEPA

3
Greenhouse Gases
CO2 is the major transportation GHG (about 95% of the overall impact) and is directly related to energy consumption
Atmospheric concentrations are growing every year because:
CO2 emissions are growing, and
CO2 has a long atmospheric lifetime (~100 years or more)
Carbon isotopes are used to distinguish CO2 from natural sources versus fossil fuel combustion
Other transportation GHGs include methane (21x more potent than CO2), nitrous oxide (310x more potent), and hydroflourocarbons (140-12,000x more potent)

Temperature Records
Three major databases of global temperatures maintained by NOAA, NASA, and CRU (England)
Thermometer records used for recent years (since ~1850), with corrections to account for heat effects of urbanization
Weather balloon, ship, buoy, and satellite measurements used in addition to land-based measurements
Proxy records (tree rings, coral, sediments, oxygen isotopes in air trapped in ice, etc.) used for earlier years
4

5
1000 years of “proxy” surface temperatures, 100+ from thermometers
Global average temperature has risen about 0.8°C (1.5°F ) over the last 125 years

6
Changes in natural systems are occurring that are consistent with rising temperatures
Some of the measured (not modeled) impacts include:
Net loss of glacial and sea ice
Rising sea level
Permafrost melt
Increases in heat waves, wildfires and floods
Increases in atmospheric water vapor
Changes in biological systems (shifting habitat zones, earlier leaf-out dates, shorter hibernation periods)
The 2007 IPCC report evaluated over 25,000 studies:
>90% show results consistent with warming

8
Observed Increases in Very Heavy Precipitation (storms > 2” of rain)
(1958 to 2007)
US GCRP, 2009

9
Common Climate Misconceptions
The “Climategate scandal” shows that the IPCC reports and other climate science can’t be trusted
The world is getting colder, not warmer
Solar radiation is the biggest contributor to climate change
Urban heat island effects are skewing the temperature record
Water vapor dwarfs the contribution of CO2 as a GHG
Climate models aren’t useful
The scientific community is evenly divided about climate change

“Climategate”
Issue: inappropriate emails between climate researchers suggesting that data manipulation could hide inconvenient results in a temperature record
This issue involved only one of three major global temperature databases, all of which show the same warming trend
It only affects the temperature record, and not any of the other data relating to climate change and its effects
Five independent reviews found no evidence of manipulation or other scientific misconduct by the researchers involved
10
EPA Endangerment Finding, 2010

“The Climate is Really Cooling, Not Warming”
11
Issue: Epic snowstorms and some temperature trends appear to indicate that the globe is cooling, not warming
The decade from 2000-2009 was the warmest on record
The winter of 2010 saw near-record warmth for the Northern Hemisphere, even with “Snowmaggedon”
Bigger snowstorms are not evidence against climate change, but an outcome of climate change
NASA Goddard Inst. For Space Studies, 2010

“It’s the Sun, Not Greenhouse Gases”
Issue: Some believe that changes in solar radiation are mainly responsible for climate change
12
But, correlation does not imply causation . . .
Calder, 1998; Briggs, 2011

13
Net climate forcings
Red bars indicate positive forcings (warming)
Blue bars indicate negative forcings (cooling)
Changes in solar radiation are a contributor, but a very small one
Warmer
Cooler
IPCC 2007

“It’s the Urban Heat Island Effect, Not Climate Change”
Issue: Measured increases in global average temperature are really a reflection of increasing urbanization around long-term weather monitoring stations
Rural stations and measurements over oceans show similar upward trends as urban stations
Weather balloon and satellite records of different levels of the atmosphere also demonstration a warming trend
Other physical data (sea level rise, sea ice melt) support the rising temperature trend
14
EPA Endangerment Finding, 2010

“Water Vapor is the Biggest GHG, Not CO2”
15
Issue: Water vapor has a much larger warming impact than other GHGs
This is true, but misleading:
The current greenhouse effect is mainly due to water vapor (without it, the Earth would be frozen to the tropics), and models take this into account
What we care about are changes in the greenhouse effect (e.g., warming beyond current conditions)
Changes in water vapor content in the atmosphere due to human activities (like combustion) are very small, and water vapor also has a very short atmospheric lifetime (around 3 days)
Most warming is due to other GHGs

“Climate Models Can’t Be Trusted”
Issue: Some believe that climate models aren’t reliable, are missing key variables, or have other flaws
Climate models are validated against current and past data (just like travel models) before being used to make future predictions
July 2008 USGCSP report concludes that “modern models faithfully simulate continental to global scale temperature patterns and trends observed during the 20th century.”
16

17
2007 IPCC Report Modeling Scenarios
Black lines show actual temperature record; blue area shows modeled change with only natural forcings; red area shows modeled change with both natural and manmade forcings.

“Scientists Are Evenly Divided about Climate Change”
Issue: Media reports portray the issue as “the climate debate”, creating the impression that there are two equal and opposing sides
A June 2010 study, peer-reviewed and published in the Proceedings of the National Academy of Sciences, examined the publication record of 1372 known climate researchers, sorted into “convinced” and “unconvinced” groups
The “unconvinced” group comprised only 2% of the top 50 researchers ranked by expertise (# of papers published in peer-reviewed journals), or 2.5% of the top 200
The average level of expertise in the “unconvinced” group was about half that of the larger “convinced” group
Researchers with fewer than 20 published papers comprised 80% of the “unconvinced” group, compared to 10% of the “convinced” group
In other words, the more experience you have as a climate researcher, the more likely you are to be convinced by the evidence of climate change.
18
PNAS, Vol.107 No. 27, 2010

19
Where are we heading?
Virtually certain(> 99% chance) that trend toward warmer weather will continue
With a doubling of atmospheric CO2 concentrations, temperature increase is likely(> 66% chance) to be in the range of 2 - 4.5 °C (4 - 8°F), very unlikely(< 10% chance) to be less than 1.5 °C (3°F).
The upper end of the likely temperature range is comparable to the temperature increase from the last ice age to today
IPCC 2007

20
Future Climate Projections
Note: the recent growth rate in global CO2 emissions is higher than any of these IPCC scenarios

21
TRB Special Report 290: Climate Change, Impacts on U.S. Transportation, and Adaptation Strategies
TRB findings on transportation impacts:
Increases in very hot days and heat waves (very likely - 90% chance)
Increases in Arctic temperatures (virtually certain – 99% chance)
Rising sea levels (virtually certain – 99%)
Increases in intense precipitation events (very likely – 90%)
20-yr peak precipitation events could occur every 6 to 8 years over much of the US
Increases in hurricane intensity (likely – 66% chance)

Improving Climate Communication
22
Try to avoid biased language:
The climate debate, the climate crisis
“Do you believein this climate change stuff?”
It’s not “just some UN thing”
The National Academies, the Transportation Research Board, USDOT, USGS, DOD, and other US agencies have published many reports about climate change in recent years
Many entities not known for environmental activism, including DOD, the insurance industry, and Fortune 500 companies, are taking climate change very seriously
Identify co-benefits of strategies (energy savings, NAAQS reductions, etc.)

TRB/National Academies Resources
TRB Modal Primer on Greenhouse Gas and Energy Issues for the Transportation Industry
Good introduction to transportation GHG issues
America’s Climate Choices series (NAS)
Four reports summarizing the state of climate science, mitigation, and adaptation approaches
Very concise and understandable fact sheets available
http://americasclimatechoices.org/
23

FHWA Resources
Educating the Public on CC Issues: DOT and MPO Best Practices
Summary of outreach activities conducted by DOTs and MPOs
Climate Change: Model Language in Transportation Plans
Climate change excerpts from actual transportation planning documents
These reports posted at www.fhwa.dot.gov/hep/climate/resources.htm
24

25
GHG Analysis Methodologies

Draft CEQ Climate Change in NEPA Guidance
CEQ issued draft guidance on consideration of climate change in NEPA, including GHG analysis, on February 18, 2010
Recommends that federal agencies address GHG emissions impacts of proposed actions where the analysis would “provide meaningful information to decision makers”
Recommends consideration of potential impacts of future climate change on proposed actions
No set timeframe for final guidance, but could be released later this year
26

Draft CEQ Guidance: When to Analyze GHG Emissions
Suggests that NEPA EA and EIS documents for proposed federal actions resulting in direct GHG emissions of 25,000 metric tons per year should include a GHG emissions analysis of alternatives
Equates to a VMT increase of roughly 125,000 miles per day as a result of a proposed project
Based on current GHG emissions rates, not including construction emissions.
CEQ doesn’t define direct emissions for mobile sources. Our initial thoughts are that for most FHWA projects, direct emissions would include construction and tailpipe emissions.
27

Draft CEQ Guidance: Greenhouse Gas Analysis
Analyze GHG emissions if agency has determined that an analysis is appropriate
Quantify direct, indirect, and cumulative emissions over life of the project
Use interagency consultation to determine best procedures for evaluation
28

Programmatic Approaches
CEQ’s draft guidance also provides for programmatic analysis
GHG emissions and potential impacts of climate on proposed actions could be analyzed at a broad scale (e.g., in the planning process), and this analysis could be cited in NEPA documents for individual projects
This is consistent with FHWA’s long-standing policy preference, which is to estimate GHG emissions at the regional level (state- or MPO-level analysis), instead of project-specific analysis
29

Greenhouse Gas Emissions from Transportation
GHG emissions from motor vehicles are directly related to energy consumption
90-95% of transportation GHG impact comes from CO2; remainder comes from other transportation GHGs (CH4, N2O, HFCs)
Without good energy/GHG analysis, don’t know if projects are increasing or reducing emissions.
Could unknowingly work against climate goals
Could invest in projects for purposes of GHG reductions that don’t actually reduce emissions, at least in a useful timeframe
30

Life-cycle Considerations
31
GHG emissions are cumulative, not episodic like other air pollutants:
CO2 will stay in the atmosphere for decades
Because of this, realistic analyses must use a lifecycle approach
Lifecycle analysis can be used to calculate payback periods (when emissions benefits from operational improvements are big enough to offset construction emissions), to compare different planning scenarios, and to ensure that projects are providing net GHG reductions by CAP target dates

Lifecycle Components for Plans and Projects
32
Direct (operational) emissions
Indirect emissions (overall impact varies)
Changes in travel activity on other roadways, mode shift
Induced/displaced land use
Construction and maintenance emissions (typically +5%, but can vary widely)
Extent of activity (earthwork, tunneling, grade reduction)
Materials (amount of steel and concrete, recycled vs virgin materials)
Fuel and vehicle cycle emissions (+40%)
Well-to-pump emissions for fuels
Manufacture and disposal emissions for vehicles

Operational Emissions:Simple, Inaccurate Analysis Approaches
33
VMT as a surrogate for GHG emissions
VMT + conversion factors (fuel economy) to estimate GHG emissions
MOBILE6.2 (CO2 emissions not adjusted for speed in this model)
Speed matters!

Operational Emissions: EPA’s MOVES model
Replacement for MOBILE6.2
Final model released 12/2009, updated 9/2010
Performs energy and GHG analysis
Can be used at regional or project level
Once MOVES is used for regional conformity, adding GHG analysis is a matter of checking a few extra boxes in the interface
34

Using MOVES for GHG Analysis: Two Options
Emission Inventory
MOVES, unlike MOBILE6.2, is an inventory model
Can calculate total energy consumption and/or GHG emissions for a selected geographic area and fleet
Look-up Table Output Option
A look-up table output option allows users to produce running emission rates in grams per mile in order to post-process results, as some agencies currently do with MOBILE
In a lookup run, MOVES produces energy or emissions rates (grams/mile, BTU/mile, etc.) for each speed bin (5 mph increments)
Results available for GHGs, energy (and mpg with post-processing)
35

MOVES Data Needs
EPA is currently drafting technical guidance for using MOVES for GHG analysis. Data needs include:
Fleet age and population
Fuel formulation and market share
Meteorology
Inspection/maintenance programs
Travel activity (speeds, VMT by vehicle type and road type, ramp fractions, VMT fractions by hour/day/month)
Defaults available for much of this
36

Other sources of emissions
Construction and Maintenance
New York has a simple lookup methodology (emissions by lane mile)
SAQMD Road Construction Model
Lots of research interest in this area
Fuel and vehicle cycle emissions
Factors based on operational emissions available from EPA and/or FHWA
37

Transportation Research Board Resources
38
NCHRP 25-25/Task 58: Methods to Address GHGs from Construction and Maintenance (report and spreadsheet tool)
http://144.171.11.40/cmsfeed/TRBNetProjectDisplay.asp?ProjectID=761
Currently active research:
GHG inventory methodologies for State DOTs
Updates to fuel cost adjustment factors for construction
SHRP2 CO9 framework for addressing CC in planning, and practitioners guide
These projects should all be completed later this year

EPA Resources
Updated COMMUTER model
Transportation GHG strategies reports
TCM guidance
OMEGA model
Available at www.epa.gov/otaq
39

FTA/APTA Resources
Transit’s Role in Responding to Climate Change
Transit GHG Emissions Management Compendium
Recommended Practice for Quantifying GHG Emissions from Transit (APTA)
These reports and others posted at www.fta.dot.gov/planning/planning_environment_12125.html
40

FHWA Resources
41
Peer Exchange/Workshop reports
Summaries of peer workshops conducted in 2008 and 2010
USDOT Report to Congress: Transportation’s Role in Reducing U.S. GHG Emissions
Exhaustive review of transportation strategies to reduce GHGs
These reports posted at www.fhwa.dot.gov/hep/climate/resources.htm
Upcoming:
GHG mitigation guidebook: methodologies for planning level GHG analysis
contract just getting underway, completion in 2012
State-level GHG analysis model
Revised version of Oregon’s GreenSTEP model, for statewide transportation GHG analysis, available later this summer

Overview of Climate Science GHG Analysis Methods and Resources

by MVRPC on Aug 02, 2011

Accessibility

Categories

Tags

Upload Details

Usage Rights

1 Embed 70

Statistics

Overview of Climate Science GHG Analysis Methods and Resources — Presentation Transcript