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ESSE
Environmental Scenario Search
Engine for the Data Services Grid
Mikhail Zhizhin, Geophysical Center
Russian Academy of Sciences
[email protected]
Eric Kihn, National Geophysical Data Center NOAA
[email protected]
www.wdcb.ru
• Geophysical Center Russian Academy of
Sciences
• World Data Centers for Solid Earth and SolarTerrestrial Physics
• Environmental data archives – paper, tapes,
files, databases, e-journals…
• International network for geophysical data
exchange with the US, Japan, China, …
• Computer center, Linux cluster, fiber optics
• Part of the European GRID infrastructure EGEE,
Russian GRID Virtual Organization e-Earth
50 years ago – International
Geophysical Year – IGY1957
World Data
Center B
World Data
Center A
Sun and
space
Sun and
space
Solid
Earth
Meteo
Mail
Meteo
Solid Earth
World Data
Center C
Total data
volume ~ 1 Gb
Exchange ~ 1 Mb/year
Satellites
Solid
Earth
Meteo
Yesterday – databases, Internet,
web – Y2K
Data
Resource
Data
Resource
Data
Resource
Data
Resource
Data
Resource
Data
Resource
Data
Resource
Data
Resource
Total data
volume ~ 1 Tb
Exchange ~ 1 Gb/year
Data
Resource
Tomorrow – Electronic
Geophysical Year – EGY2007
Data
Resource
Data
Resource
Data
Resource
Data
Resource
GRID
Data
Resource
Total data
volume ~ 1 Pb
Exchange ~ 1 Tb/year
Data
Resource
Data
Resource
Data
Resource
SPIDR – Space Physics Interactive
Data Resource
Kamchatka
Moscow
Boulder
Beijing
Nagoya
SPIDR 3
SPIDR 2
Grahamstown Sydney
http://spidr.ngdc.noaa.gov
Cross-disciplinary data exchange
da
Space
ta
queries
data
?
Atmosphere
results
User
data
Ocean
da
Geology
•
Users need data from different disciplines
•
Rapid growth of the data volume and data
demand requires new tools for the data
management and the data mining
ta
“Metcalfe’s law” for databases
• The utility of N independent data sets seems to
increase super-linearly
• One can find N(N-1) ≈ N2 relations
between data sources, that is their
utility grows ≈ N2
Utility
• It is more efficient ot use several
data sources than one archive
1
2
3
4
Nubmer of data sources
5
6
Sources of data inflation?
1.
2.
3.
New versions
Derived data products
Reanalysis
Products of Level 1 (NASA terminology) take 10% of the Level 0 volume, but
the number of the Level 1 products is increasing. If the volume of the Level 0
data grows as N, then the volume of Level 1 data is growing as N2.
18
16
Data, Tb
14
12
Level 0
10
Level 1
8
Level 0 + Level 1
6
4
2
0
1
2
3
4
5
6
7
Years
8
9 10 11 12 13
Observations + Model = Reanalysis
1. Direct observations, including raw and
processed data, e.g. meteorological station or
satellite.
2. Numerical model “knows” physics, uses direct
observations as boundary values, e.g. Global
Circulation Model. Input data volume (irregular
grid) is less than the output volume (regular
grid).
3. Reanalysis – accumulated output of the
numerical model runs based on the direct
observations for a long time period, say 50
years.
D-day reanalysis – morning
(after ECMWF)
June 6th, 1944, midnight
June 6th, 1944, 6 AM
D-day reanalysis – evening
(after ECMWF)
June 6th, 1944, 12 AM
June 6th, 1944, 6 PM
Data inflation after reanalysis
• Modern global atmospheric circulation model
(GCM) at 2.5o (latitude) x 2.5o (longitude) x 20
(levels) = 106 gridpoints.
• GCM outputs "high-frequency" data every six
hours of simulation time, so ~ 1 Gb of data per
simulation day .
• By contrast, the world-wide daily meteorological
observational data collected over the Global
Telecommunications System, is ~ 200 Mb.
• As an extreme, to run the GCM for 50 years of
simulation time will provide 40 Tb of data.
Space Weather Reanalysis
Input: ground and satellite
data from SPIDR
Space weather numerical models
TIEGCM
Init Conditions
IMF
Kp
Dst
10.7 cm Flux
HPI
Magnetometer
GOES
AMIE
Magnetic, Electric Potential, Etc.
High Lat Elec
Geostationary Magnetic Field, Kp
TEC, FoF2,Neutral Winds
MSM
SWR
DATA
Particle Data
Output: high-resolution
representation of the
near-Earth space
ESSE solutions
•
•
•
•
Do not use data files, use distributed databases
Optimize data model for the typical data request
Virtualize data sources using grid (web) services
Metadata schema describes parameters, grids,
formulas for virtual parameters (e.g., wind speed
from U- and V-wind)
• Search for events in the environment by the
“scenario” in natural language terms
• Translate the scenario into the parallel request
to the databases using fuzzy logic
ESSE architecture
•
•
•
•
Fuzzy logic engine performs
searching and statistical
analysis of the distribution of
the identified events
Parallel mining of several
distributed data sources,
possibly from different subject
areas
Both the fuzzy logic engine
and data sources
implemented as Grid (web)
services
Interfaces and data structures
can be obtained from the
definitions of the web-services
(WSDL)
Terrestrial
Weather
Web Service
Data
List of events
Client
Fuzzy Search
Web Service
Data
Space Weather
Web Service
Data
Digital Terrain
Web Service
•
Web services and prototype user
interface are installed on two mirror
servers:
− Boulder, US
− Moscow, Russia
Parallel database cluster
(NCEP reanalysis)
Select Temperature in April for years 2N+3 to
3N+1
(e.g., 1993-2001)
Years:
1
N+1
2N+1
...
Years:
2
N+2
2N+2
...
Years:
3
N+3
2N+3
...
...
Years:
N
2N
3N
...
ESSE “time series” data model
Indexed lat-lon grids of
time series in BLOBs
What is fuzzy logic?
• Fuzzy logic uses set membership values between and
including 0 and 1, allowing for partial membership in a
set.
• Fuzzy logic is convenient for representing human
linguistic terms and imprecise concepts (“slightly”,
“quite”, “very”).
Fuzzy membership functions
What good is fuzzy logic for ESSE?
• Fuzzy engine allows to build queries in human linguistic
terms:
(VERY LARGE “wind speed") AND
(AVERAGE "surface temperature") AND
(“relative humidity“ ABOUT 60%)
• You can use the same terms for different value ranges:
AVERAGE TEMPERATURE for Africa is not the same as for
Syberia.
• Results are given as a list of “most likely” events. Each
event is assigned a value, representing its “likeliness”.
January Wind Speed Record
Wind Speed (kts)
20
“High”
Wind
15
10
5
0
1/1/97
1/6/97
1/11/97
1/16/97
1/21/97
1/26/97
1/31/97
Date
Temperature (deg C)
January Temperature Record
“Average”
Temperature
30
25
20
15
10
5
0
1/1/97
1/6/97
1/11/97
1/16/97
1/21/97
1/26/97
1/31/97
Date
Rel. Humidity (%)
January Relative Humidity Record
100
80
“About” 60%
Humidity
60
40
20
0
1/1/97
1/6/97
1/11/97
1/16/97
Date
1/21/97
1/26/97
1/31/97
Prototype workflow and UI
• Prototype UI implemented as a web-application
• Discover data sources by keyword-based metadata
search
• Use predefined weather events (e.g. “ice storm”, “flood”)
• Define the event as a combination of fuzzy conditions on
a set of environmental parameters (e.g. “high
temperature and low relative humidity”)
• Review statistics for the detected events
• Visualize the selected event as time series plots or
contour maps
• Download the event data in self-describing format
(NetCDF or HDF) to the user’s workstation
Setting spatial locations
Select a set of "probes" (representing spatial locations of interest, e.g.
New York) where the desired event may occur.
Defining fuzzy search criteria
• Select several parameters for the event from a list.
Set the fuzzy constraints on the parameters for the event (e.g. “very
high temperature”, “very high humidity”).
Working with scenarios
The user may search for a desired scenario by describing several
subsequent events
Search Results
• “Score” represents the “likeliness” of each event in a numerical form.
• The results page provides links to visualization and data export
pages.
Visualizing event as time series
Visualizing event in 5D
Visualizing event from satellites
What do we get at the end?
• Using the “time machine”, we can see the
weather on the D-day, or the Rita hurricane, or
the typical September day in San Diego.
• Statistics to estimate risk from natural disasters,
global climate change, realistic weather in
movies, computer games, simulators
• When Tim Berners-Lee uses semantic web to
find a photo of the Eiffel Tower on a sunny
summer day, ESSE can provide a list of sunny
days to be merged with the list of images named
with “eiffel”