Help and Frequently Asked Questions
The paper describing the development of the newly added Erosivity and Moisture related variables has been submitted for peer review: Dissecting the Aridity Index for assessing
global climate change, Girvetz et al. Upon publication we will provide the citation here. In the meantime please see the list of citations we used to both develop the enhanced moisture calculations and write the manuscript. The citations are available in PDF format in the link below.
We believe it is
critical for Climate Wizard users to familiarize themselves with the strengths
and limitations of the available data and the appropriateness of applying Climate
Wizard’s various analytical techniques to any particular data set.
Here we provide an overview of important
information and caveats in the Use and Misuse of Climate Data and Analysis
presented in the Climate Wizard.
2.
Who can I contact for additional information?
3. How do I draw a polygon on the map?
4.
How do I erase a polygon on the map?
5.
Can I turn the map display off?
7.
How do I move the map and zoom in
and out?
8.
Can I select multiple regions in
the “Add Pre-Defined Areas” dialogue box?
9.
Time periods - What should I know when selecting them?
10.
Can I select more than one
climate variable?
11.
Can I select more than one
General Circulation Model?
12.
Can I select more than one
emissions scenario?
13.
What is
the resolution, projection, and units of the data I downloaded?
14.
Can I change the base map in the results webpage?
15.
Can I change the map
transparency in the results webpage?
19.
How do I download and import map
images in ArcGIS?
20.
What is IPCC Fourth Assessment?
21.
What are Emission Scenarios?
22.
What are General Circulation Models
and where can I learn more?
23.
What is Ensemble in the General
Circulation Models list?
24.
What does the graph show and what do
the colored lines represent?
25.
How do I cite the data used in the
Climate Wizard?
26.
What is the
resolution, projection, and units of the data I downloaded?
28. I downloaded the data - How do I interpret the file names?
29. Moisture Variables - Definitions and citation
Developed through collaboration between
The Nature Conservancy, The University of Washington, and The University of
Southern Mississippi, the Climate Wizard enables technical and non-technical
audiences alike to easily and intuitively access leading climate change
information and visualize the impacts anywhere on
Earth.
Climate Wizard Custom is a new tool where a user can define a relatively small geographic area of interest and conduct site-specific analyses using both historical data and possible future conditions that are based on low (B1), moderate (A1B), and high (A2) carbon emissions scenarios. Sixteen general circulation models are available to provide a range of possible outcomes, and users can analyze absolute and percentage changes in annual, seasonal or monthly climate conditions in graphic or map form. Since the large climate datasets are stored and analyzed remotely on powerful computers, users of the tool do not need to have fast computers or expensive software, but simply need access to the internet. Using web technologies to develop tools that make climate change analysis more accessible scientists, managers, and policy makers now have the ability to assess the potential impacts of climate change and help guide decisions and actions to prepare for and mitigate those impacts to natural systems and the services they provide.
2. Who
can I contact for additional information?
For general questions and
information on development staff, please email climateportal@worldbank.org
3.
How do I draw a polygon on
the map?
Press the icon (outlined in red) located to the upper left of the
map. Click on the map to place the
polygon nodes. Double click to complete
the polygon.
4. How do I
erase a polygon on the map?
Press the icon (outlined in red) located to the upper left of the map.
5.
Can I turn the map display off?
Press the icon (outlined in red) located to the upper left of the map.
Press the plus symbol located on the upper right of the map.
7.
How do I move the map and zoom in and out?
Press the icon (outlined in red) located to the upper left of the
map. Then click and drag your cursor on
the map to pan the image. You can also
press the icon located in the
upper left corner of the
map. To zoom
in, press the icon outlined in red and double-click
the map. You can also press the icon
located in the upper left corner of the map to zoom in and out and refresh the
8.
Can I select multiple regions in the “Add Pre-Defined Areas”
dialogue box?
Yes,
press and hold the control button for individual multiple selections or press and hold the shift key for a group
selection.
9.
Time Periods - What should I know when selecting them?
Meaningful statistical representations of modeled future climate predictions are best achieved by examining a range of time rather that a single year. For example, in the Climate Wizard main page we have chosen the time period 2040-2069 and 2070-2099 to provide the user with a range that most accurately describes the predicted conditions for the mid century (2050) and the end of the century (2100) respectively. Please read the Use and Misuse of Climate Data and Analysis for more information.
10. Can I
select more than one climate variable?
Yes,
check the box to the left of the desired climate variables.
11. Can I
select more than one General Circulation Model?
Yes,
hold down the shift or control button to select all or individual models.
12. Can I
select more than one emissions scenario?
Yes,
check the box to the left of the desired emissions scenario.
13. What are
the resolution, projection, and units of the data I downloaded?
The grid cell resolution of the GIS data contained in the downloaded
file is identical to the resolution of the input dataset selected by the user
as indicated on the Climate Wizard homepage.
The user may click on the text to review a complete data description.
14. Can I change the base
map in the results webpage?
Press the plus symbol located on the upper right of the map to reveal base map layer options such as satellite or streets view.
Drag the slider to reduce or
increase the transparency of the climate map layer to reveal the elements of
the base map image below
Use the pull-down arrow to quickly
move to another state or country in the current map view.
The map of average shows the mean
temperature or precipitation value for the time period.
For maps showing the historical
climate (present day and before) the “change” describes how climate has
generally changed over time. This is a trend analyses that describes the
average change in climate per year over a given entire period.
For maps showing the future
predicted climate (present day and beyond) the “change” is a comparison between
the future climate to a baseline time period (climatic departures). In the case
of the Climate Wizard the baseline is the present-day conditions or more
accurately the average temperature and precipitation between 1961 and 1990 -- (how
different will the conditions be in the future from today?).
19. How do I download and import map images in ArcGIS?
Data (GIS format) – This download
option allows the user to save a GIS ready file to their computer. The format
of the file is ASCII (float) which can be imported in most GIS applications. To
import the data into ArcGIS follow the directions
below:
1. In ClimateWizard,
display exactly the data you want to download, then
click the Data option from ClimateWiz menu. Save the
file with .asc extension (if you
don’t have this option, save as .txt and then rename the file with the
extension changed to .asc).
2. In ArcGIS,
open ArcCatalog, then open ArcToolbox.
3. In ArcToolbox,
go to Conversion Tools→To Raster→ASCII
to Raster→Input ASCII Raster File. Navigate to
your downloaded .asc file. Your Output Raster file
should be renamed with 13 letters or less, leaving the extension blank (this
will give you a GRID file, which is easiest to use for math). The Output Data
Type must be set to FLOAT.
4. In the ArcToolbox,
go to Data Management→Tools→Projections
and Transformations→Define Projection. Select
your new file for input.
5. Under Coordinate System, select
Geographic Coordinate Systems→World→WGS
1984.prj.
6. The file is now ready to add to
your ArcGIS project using the Add Data button.
Map Image – You can click on map
image to open a separate web browser window showing only the climate map and
legend (without the Google Earth background) or you can right-click on map
image and save the graphics file to your computer.
20. What is the IPCC Fourth Assessment?
The IPCC was established to provide
the decision-makers and others interested in climate change with an objective
source of information about climate change. The IPCC does not conduct any
research nor does it monitor climate related data or parameters. Its role is to
assess on a comprehensive, objective, open and transparent basis the latest
scientific, technical and socio-economic literature produced worldwide relevant
to the understanding of the risk of human-induced climate change, its observed
and projected impacts and options for adaptation and mitigation http://www.ipcc.ch/. A suite of international modeling groups provided modeled
climate projections that was used in this report; published in 2008.
21. What are Emission Scenarios?
A scenario is a coherent, internally
consistent and plausible description of a possible future state of the world.
It is not a forecast; rather, each scenario is one alternative image of how the
future can unfold. A projection may serve as the raw material for a scenario,
but scenarios often require additional information (e.g., about baseline
conditions). A set of scenarios is often adopted to reflect, as well as
possible, the range of uncertainty in projections. Other terms that have been
used as synonyms for scenario are "characterization",
"storyline" and "construction". (http://www.ipcc-data.org/ddc_definitions.html). Look here
or more information on Emission Scenarios
22. What are General Circulation Models and where can I find
more information?
Climate models use quantitative
methods to simulate the interactions of the atmosphere, oceans, land surface,
and ice. They are used for a variety of purposes from study of the dynamics of
the weather and climate system to projections of future climate. All climate
models balance, or very nearly balance, incoming energy as short wave
electromagnetic radiation (visible and ultraviolet) to the earth with outgoing
energy as long wave (infrared) electromagnetic radiation from the earth. Any
imbalance results in a change in the average temperature of the earth. Look here or more information on General Circulation Models. The
following is a list of the models presented in the Climate Wizard. This list is
extracted from the information provided by the Program for Climate Model
Diagnosis and Intercomparison Coupled Model Intercomparison Project (CMIP3) Climate Model Documentation
website.
|
Norway |
Bjerknes Centre for Climate Research |
|
|
Canada |
Canadian Centre for Climate Modelling & Analysis |
|
|
France |
Météo-France / Centre National de Recherches
Météorologiques |
|
|
Australia |
CSIRO Atmospheric Research |
|
|
USA |
US Dept. of Commerce / NOAA /
Geophysical Fluid Dynamics Laboratory |
|
|
USA |
US Dept. of Commerce / NOAA /
Geophysical Fluid Dynamics Laboratory |
|
|
USA |
NASA / Goddard Institute for Space
Studies |
|
|
Russia |
Institute for Numerical
Mathematics |
|
|
France |
Institut Pierre Simon Laplace |
|
|
Japan |
Center for Climate System Research
(The University of Tokyo), National Institute for Environmental Studies, and
Frontier Research Center for Global Change (JAMSTEC) |
|
|
Germany / Korea |
Meteorological Institute of the
University of Bonn, Meteorological Research Institute of KMA, and Model and
Data group. |
|
|
Germany |
Max Planck Institute for
Meteorology |
|
|
Japan |
Meteorological Research Institute |
|
|
USA |
National Center for Atmospheric
Research |
|
|
USA |
National Center for Atmospheric
Research |
|
|
UK |
Hadley Centre for Climate
Prediction and Research / Met Office |
23. What is Ensemble in the General Circulation Models list
(GCM)?
Climate change analysis becomes more
complex for the future than the past because there is not one time-series of
climate, but rather many future projections from different GCMs run with a
range of CO2 emissions scenarios (IPCC 2007b). It is important not to analyze
only one GCM for any given emission scenario, but rather to use ensemble
analysis to combine the analyses of multiple GCMs and quantify the range of
possibilities for future climates under different emissions scenarios. There
are many approaches for doing ensemble analysis ranging from simple averaging
approaches to more complex and computationally intensive probability estimation
approaches (Dettinger 2006, Araujo
and New 2007). Here, we used a fairly simple, yet informative non-parametric quantile-rank approach that maps out the 0 (minimum), 20,
40, 50 (median), 60, 80, and 100th (maximum) percentiles (Figures 6 and 7).
While all models agree that mean temperatures will increase everywhere in the
world (Figure 6), they often do not agree on the magnitude of that increase.
The term Ensemble Average located in the General Circulation
Model (GCM) pull-down list on the ClimateWizard home
page displays the 50th percentile or median prediction of all subsequent GCMs
listed.
24. What does the graph show and what do the colored lines
represent?
The graph shows the yearly values of
the climate variable selected. The blue line is the 5-year rolling average. The
red line is the shows the trend or rate of change over the time period shown.
25. How do I cite the data used in the Climate Wizard?
The primary citation for the Climate Wizard Custom Analysis Application can be found here - Applied Climate-Change Analysis: The Climate Wizard Tool. Please also see the About Us section of the Climate Wizard home page for additional information and citations. For further questions please contact climatewizard@tnc.org
26. What are the resolution, projection, and units of the data I
downloaded?
The grid cell resolution of the GIS
data is indicated on the Climate Wizard data information page documentation.html. The projection and units correspond to Geographic, WGS 84.
The following was taken from Maurer,
E. P., L. Brekke, T. Pruitt, and P. B. Duffy (2007),
Fine-resolution climate projections enhance regional climate change impact
studies, Eos Trans. AGU, 88(47), 504 and describes the data presented the the ClimateWizard:
A statistical technique was used to
generate gridded fields of precipitation and surface air temperature over the
conterminous United States and portions of Canada and Mexico. The method
involves (1) a quantilemapping approach that corrects
for GCM biases, based on observations of 1950–1999; and (2) interpolation of
monthly bias-corrected GCM anomalies onto a fine-scale grid of historical
climate data, producing a monthly time series at each 1/8-degree grid cell. The
method has been used extensively for hydrologic impact studies (including many
with ensembles of GCMs) and in a variety of climate change impact studies on
systems as diverse as wine grape cultivation, habitat migration, and air
quality.
The downscaled data are freely
available for download at the Green Data Oasis, a large data store at LLNL for
sharing scientific data (http://gdo-dcp.ucllnl.org/downscaled_cmip3_projections/).
Users can specify particular models,
emissions scenarios, time periods, geographical areas, and raw data or summary
statistics. All data are archived in a standard netCDF
format, a self-describing machine-independent format for sharing gridded
scientific data. The full text of this article can be found in the electronic
supplement to this EOS issue (http://www.agu.org/eos_elec/).
28.
I downloaded the data - How do I interpret the file names?
The ascii files you download follow the naming conventions described below:
Historical analyses: name = DataType_VariableName_Month_StartYr_EndYr:
Future analyses: name = DataType_ModelName_ScenarioName_VariableName_Month_StartYr_EndYr
Month Codes:
| Month Number | Month Name |
| 1 | January |
| 2 | February |
| 3 | March |
| 4 | April |
| 5 | May |
| 6 | June |
| 7 | July |
| 8 | August |
| 9 | September |
| 10 | October |
| 11 | November |
| 12 | December |
| 14 | Annual |
| 15 | Dec-Feb |
| 16 | March-May |
| 17 | June-Aug |
| 18 | Sept-Nov |
Variable names, abreviations, and units:
| Variable | Abbrevation | Metric Units | English Units |
| Precipitation | ppt | Millimeters | Inches |
| Mean Temperature | tmp | Celcius | Fahrenheit |
| Minimum Temperature | tmin | Celcius | Fahrenheit |
| Maximum Temperature | tmax | Celcius | Fahrenheit |
| Moisture Surplus | surpHam | Millimeters | Inches |
| Moisture Deficit | defHam | Millimeters | Inches |
| PET (Potential Evapotranspiration) | petHam | Millimeters | Inches |
| AET/PET (ratio) | aetToPetHam | Ratio | Ratio |
29.
Moisture Variables - Definitions and citation
The balance between precipitation and the amount of water that an ecosystem could potentially use though evaporation and transpiration— potential evapotranspiration—is the basis for the moisture metrics used here: the Aridity Index, climate moisture surplus, and climate moisture deficit. This can be generally thought of as the balance of water in a system, between the supply of water (precipitation) and demand of water (potential evapotranspiration).
Potential Evapotranspiration (PET) is a metric representing the water that an ecosystem could potentially use though evaporation and transpiration. PET was calculated based on monthly temperature and monthly average number of daylight hours based on a modified version of the Thornethwaite equation (Hamon, 1961). PET is higher with warmer temperatures and more daylight hours. See Wolock and McCabe (1999) for more details on the approach.
Climatic moisture surplus is a metric quantifying excess water in a system—it can be a gross surrogate for water runoff and stream/river flows. When we calculate it here, surplus occurs only when precipitation is greater than PET in a given month; it is the amount of precipitation that falls above and beyond PET (measured in mm). The concept of surplus is that the precipitation that falls below the PET amount is evaporated or transpired by the system and does not runoff over the surface or infiltrate into the soil. However, if more water falls than PET, then the excess precipitation above and beyond PET is the surplus that turns into runoff or ground water infiltration. Surplus is calculated as PPT minus PET within each month—and set to zero if less than zero (i.e. no surplus in a month)—then summed over all months for a given season or year.
Climatic Moisture deficit is a metric quantifying moisture stress in a system—it is very closely related to the Aridity Index—higher moisture deficit reflects higher moisture stress. Deficit only occurs only when precipitation is less than PET in a given month; it is the gap between the amount of precipitation and PET (measured in mm). The concept of moisture deficit is that there is greater evaporative demand than there is precipitation that falls and the system desires more moisture. If precipitation decreases or temperature increases (increasing PET) moisture deficit increases. The greater the moisture deficit the greater the gap between precipitation and PET. Deficit is calculated as PET minus precipitation (in mm)—and set to zero if precipitation is greater than PET—then summed over all months for a given season or year.
Aridity index (modified version) is a metric quantifying moisture stress and aridty in a system—it is very closely related to moisture deficit—lower aridity index represents higher moisture stress. It is calculated as the ratio between precipitation and PET summed over all months for a given year (or season), with the modification that precipitation is capped at PET for each month. Similar to how deficit is calculated, if precipitation in a given month is greater than PET, it is capped at the value of PET (no surplus is considered when calculating this version of the Aridity Index).
Reference: Wolock, D. M. and G. J. McCabe. 1999. Explaining spatial variability in mean annual runoff in the conterminous United States. Climate Research 11:149-159.