navarro c - downscaling of gcm for i’ts use in agriculture and nrm research
DESCRIPTION
CCAFS Date: 10/10/2012 Place: CIATTRANSCRIPT
Carlos Navarro, Julian Ramirez,Andy Jarvis, Peter Laderach
Downscaling of GCM for i’ts use in Agriculture and NRM Research
Cali, Colombia CIAT10/10/2012
• Brief about climate & agricultre
• Climate data, availability, difficulties, options
• Our databases
Contents
•Any agroecosystem respond to changes of anthropogenic factors, biotics, abiotics.•Weather and climate predictability is fairly limited. • The climate will change.• Each system is an specific case. •Crops are very sensitive to climatic conditions
The demand – CertaintyWe know…
Climate & Agriculture– Multiple variables– Very high spatial
resolution– Mid-high temporal (i.e.
monthly, daily) resolution– Accurate weather
forecasts and climate projections
– High certainty• Both for present and
future
–T°• Max,• Min, • Mean
–Prec–HR– Radiation– Wind– …….
Less
impo
rtan
ce
Mor
e ce
rtai
nty
The demand – Certainty
>> UNCERTAINTIES
We don’t know… What are the conditions in 30, 50, 100 years?
• How our system respond to these conditions?
• When, where and what type of change requiere to adapt?
• Who should plan? Who should leads the process ? Who should run?
The demand – Certainty
Reliable climatic data Gaps in representation of
the climate system
Inadequate climate models
Assessment of impacts of
climate change on agriculture
High degree of uncertainty
>> Uncertainty
Needs Limitations
The demand – Certainty
How to predict the future?
Economic
Environmental
Global Regional
Pessimistic“Bussiness as usual”
OptimisticPerfect World
IntermediateP
E
P
E
P
E
P
E
Emission Scenarios
In agriculture, the different emission scenarios are not important ... by
2030 the difference between the scenarios is
minimal
Key Message
GCMs are the only way we can predict the future
climate
Using the past to learn for the future
The ModelsGCM “Global Climate Model”
Variations of the Earth’s surface temperature: 1000 to 2100
What are saying the models?
Anthropogenic changes lead to changes in weather
Atmospheric concentrations
The Models
GCM - Limitations
Global scale Regional or local scale
Resolutions
• Horizontal resolution 100 to 300 km • 18 and 56 vertical levels
Model Country Atmosphere OceanBCCR-BCM2.0 Norway T63, L31 1.5x0.5, L35CCCMA-CGCM3.1 (T47) Canada T47 (3.75x3.75), L31 1.85x1.85, L29CCCMA-CGCM3.1 (T63) Canada T63 (2.8x2.8), L31 1.4x0.94, L29CNRM-CM3 France T63 (2.8x2.8), L45 1.875x(0.5-2), L31CSIRO-Mk3.0 Australia T63, L18 1.875x0.84, L31CSIRO-Mk3.5 Australia T63, L18 1.875x0.84, L31GFDL-CM2.0 USA 2.5x2.0, L24 1.0x(1/3-1), L50GFDL-CM2.1 USA 2.5x2.0, L24 1.0x(1/3-1), L50GISS-AOM USA 4x3, L12 4x3, L16GISS-MODEL-EH USA 5x4, L20 5x4, L13GISS-MODEL-ER USA 5x4, L20 5x4, L13IAP-FGOALS1.0-G China 2.8x2.8, L26 1x1, L16INGV-ECHAM4 Italy T42, L19 2x(0.5-2), L31INM-CM3.0 Russia 5x4, L21 2.5x2, L33IPSL-CM4 France 2.5x3.75, L19 2x(1-2), L30MIROC3.2-HIRES Japan T106, L56 0.28x0.19, L47MIROC3.2-MEDRES Japan T42, L20 1.4x(0.5-1.4), L43MIUB-ECHO-G Germany/Korea T30, L19 T42, L20MPI-ECHAM5 Germany T63, L32 1x1, L41MRI-CGCM2.3.2A Japan T42, L30 2.5x(0.5-2.0)NCAR-CCSM3.0 USA T85L26, 1.4x1.4 1x(0.27-1), L40NCAR-PCM1 USA T42 (2.8x2.8), L18 1x(0.27-1), L40UKMO-HADCM3 UK 3.75x2.5, L19 1.25x1.25, L20UKMO-HADGEM1 UK 1.875x1.25, L38 1.25x1.25, L20
Uncertainties!
GCM - Limitations
Difficulty 1. They differ on resolution
GCM - Limitations
• Difficulty 2. They differ in availability (via IPCC)WCRP CMIP3 A1B-P A1B-T A1B-Tx A1B-Tn A2-P A2-T A2-Tx A2-Tn B1-P B1-T B1-Tx B1-Tn
BCCR-BCM2.0 OK OK OK OK OK OK OK OK OK OK OK OKCCCMA-CGCM3.1-T63 OK OK NO NO NO NO NO NO OK OK NO NOCCCMA-CGCM3.1-T47 OK OK NO NO OK OK NO NO OK OK NO NOCNRM-CM3 OK OK NO NO OK OK NO NO OK OK NO NOCSIRO-MK3.0 OK OK OK OK OK OK OK OK OK OK OK OKCSIRO-MK3.5 OK OK OK OK OK OK OK OK OK OK OK OKGFDL-CM2.0 OK OK OK OK OK OK OK OK OK OK OK OKGFDL-CM2.1 OK OK OK OK OK OK OK OK OK OK OK OKGISS-AOM OK OK OK OK NO NO NO NO OK OK OK OKGISS-MODEL-EH OK OK NO NO NO NO NO NO NO NO NO NOGISS-MODEL-ER OK OK NO NO OK OK NO NO OK OK NO NOIAP-FGOALS1.0-G OK OK NO NO NO NO NO NO OK OK NO NOINGV-ECHAM4 OK OK NO NO OK OK NO NO NO NO NO NOINM-CM3.0 OK OK OK OK OK OK OK OK OK OK OK OKIPSL-CM4 OK OK NO NO OK OK NO NO OK OK NO NOMIROC3.2.3-HIRES OK OK OK OK NO NO NO NO OK OK OK OKMIROC3.2.3-MEDRES OK OK OK OK OK OK OK OK OK OK OK OKMIUB-ECHO-G OK OK NO NO OK OK NO NO OK OK NO NOMPI-ECHAM5 OK OK NO NO OK OK NO NO OK OK NO NOMRI-CGCM2.3.2A OK OK NO NO OK OK NO NO OK OK NO NONCAR-CCSM3.0 OK OK OK OK OK OK OK OK OK OK OK OKNCAR-PCM1 OK OK OK OK OK OK OK OK OK OK OK OKUKMO-HADCM3 OK OK NO NO OK OK NO NO OK OK NO NOUKMO-HADGEM1 OK OK NO NO OK OK NO NO NO NO NO NO
GCM - Limitations
Difficulty 3. Limited ability to represent present climates
Relying on a single GCM is dangerous!
GCM - Limitations
How I can use this information?
Problem
Needs
OptionsDownscaling by
statistical or dynamical methods..
To increase resolution, uniformise, provide high resolution and contextualised dataEven the most
precise GCM is too coarse (~100km)
GCM - Limitations
The Delta Method
Options – Statistical Methods
• Use anomalies and discard baselines in GCMs– Climate baseline: WorldClim– Used in the majority of studies– Takes original GCM timeseries– Calculates averages over a baseline and
future periods (i.e. 2020s, 2050s)– Compute anomalies– Spline interpolation of anomalies– Sum anomalies to WorldClim
Options – Statistical Methods
Stations by variable:• 47,554
precipitation • 24,542
tmean • 14,835
tmax y tmin
- 3 0 .1
3 0 .5
M e a n a n n u a lt e m p e r a t u r e ( º C )
0
1 2 0 8 4
A n n u a l p r e c i p i t a t i o n ( m m )
What is WorldClim?
Sources:•GHCN•FAOCLIM•WMO•CIAT•R-Hydronet•Redes nacionales
– They use outputs of GCMs
– Area are limited .. Need boundary conditions.
– Performs calculations of atmospheric dynamics and solve equations for each grid.
– Daily data– Resolution varies between 25-
50km– More than 170 output variables
Options – Dynamical Methods
RCM PRECIS Providing REgional Climates for Impacts Studies
Options - Comparissons
Which one is the best?Method + -
Statistical downscaling
*Easy to implement* resolutions*Apply to all GCMs*Uniforme baseline
* Change variable only at big scale* Variables do not change their relations with time* variables
Dynamic downscaling
* Robust*Apply to GCMs if data available* variables
*Few platforms (PRECIS, CORDEX)*Many processes and stockages*Limited resolution (25-50km)*Missing development*Dificulty to quantify uncertainties
GCMs
Effective adaptation options
MarkSim
DSSAT
Statistical Downscaling
Dynamical downscaling:Regional Climate Model
EcoCropStatistical Downscaling
MaxEnt
We need models to quantify the impacts and adaptation options for effective design
Based on niches
Prob
abili
ty
Environmental gradient
Based on process
Impacts
Changes in climate affect the adaptability of crops…
Number of crops with more than 5% loss
Number of crops with more than 5% gain
Impacts
There will be winners…
…But much more losers in developing countries
http://ccafs-climate.orgCCAFS Climate
CCAFS Climate - Users
• Downscaling is inevitable.• Continuous improvements are
being done• Strong focus on uncertainty
analysis and improvement of baseline data
Conclusions
• We need multiple approaches to improve the information base on climate change scenariosDevelopment of RCMs (multiple: PRECIS not enough)Downscaling empirical, methods HybridsWe tested different methodologies