Managing the Temporal Geography of Futures
Michael Flaxman, MIT
Motivation
Overview
Alternative Futures Methodology
Current Scenario & Impact Model Data Management
Four Problems
Two (Partial) Solutions
Problem 1: Too Many Futures!
Problem 2:Logical Dependencies Are Important
Correct Interpretation often depends on understanding underlying assumptions
Large Update Problems
– Scenarios dependencies propagate
– If dependencies are not tracked, danger of false attribution
Problem 2:Logical Dependencies Example
– Scenario 1 (S1) Impact of S1 on Hydrology Impact of Hydrology under S1 on Species Habitat
– Scenario 2 (S2) Impact of S2 on Hydrology Impact of Hydrology under S2 on Species Habitat
If Scenarios Change…
– Dependencies propagate i.e.above must recompute hydrology twice & habitat twice
– If dependencies are not tracked, danger of false attribution i.e. Species Habitat map not correctly updated to S1v17
Problem 3:Sharing
Creating a single isolated system to manage spatiotemporal data is hard
Creating a networked system is much harder still!– Must track dependencies *between* systems– Must deal with broken connections, latencies, and
time changes
Problem 3:Sharing Example
Parties Involved– Hydrologist at USGS (Ft. Lauderdale) – Land Use Modeler at UFL (Gainsville)– Habitat Specialists at FWS (Vero Beach & 2 Refuges)– Vegetation Specialist at Everglades National Park
Action– Land Use Modeler receives updated demographic estimate, updates land
cover model
One scenario change requires sequential notification to 5 distributed parties + manager
Problem 4:Metaphors & Mechanisms Are Weak
Available object “metaphors” and mechanisms– Files (on disk)
Bundled by space, discrete for each time ‘slice’ NetCDF – multidimensional file format
– Supported by climate models, some GIS– Not well supported outside of science
– Layers (in GIS) User re-orderable with occlusion (for better and worse) Independent visibility toggle
– Hierarchical Folders (both) Allows development of hierarchical file or layer representations of time
Other Metaphors & Concepts– Time Line”
Understandable interface, but not sharable implementation– Dependency Diagram
Again, well understood, but each implementation separate
MIT Prototypes ScenarioCMS
– A content management system for spatial scenarios organized as “time slices”
– Provides “ScenarioXML” language to document assumptions and dependencies
– Status: working prototype (Telluride), Phase 2 (BajaEcoInfo)
EverView2– Extension of ScenarioCMS for the Everglades– Visualizes & manages assumptions, choices and dependencies– Organizes “stories” within Scenarios
Stories are complex sub-scenarios with temporal sequencing – Status: early schematic
ScenarioCMS: Scenarios & Constraints
ScenarioXML
Vendor-neutral, software-neutral Organizes scenarios logically
– Like HTML, separates presentation from data– Metadata for scenario (machine & human
readable)
ScenarioCMS: Simple Time Slider
ScenarioCMS: Dynamic Legend
Florida EvergladesDis-integrated Management Systems
Water Manager’s View: Pipes Only
Refuge Manager’s View: Habitat & Species Observation Only
Scenario 1Conditions:Wet SeasonHurricane IV approachingLoxahatchee NWR and Miami-Dade at High Flood-Risk
Management Options:
A.
Miami-Dade Impact:Flood-risk reduced
Loxahatchee NWR/Everglades Impact:Flood-risk reduced
Caloosahatchee Estuary and St. Lucie Estuary Impacts:Water quality decreasesLow O2 levelsFish KillInundate Sea Grass
Urban Flood-Risk LevelsL M H
Conservation Areas Flood-Risk Levels L M H
Lake Okechobee Water Level14.5’ 16.5’ 17.5’
release
Lock
timeline
Flood-risk high
Release to C-44 and C-43
Water reaches first locks, Port Mayaca, Moore Haven
Water reaches St. Lucie Lock
Water reaches Franklin Lock
Urban flood-risk reduced; Estuarine Impacts
A.
Release water toC-43 and C-44 St. Lucie Canal; Caloosahatchee Canal
B.
Release water toL-8 and L-10 STA 1-W and 1-E; WCA 1 (Lox. NWR)
Decision Impacts:
Preview Preview
Scenario 1Conditions:Wet SeasonHurricane IV approachingLoxahatchee NWR and Miami-Dade at High Flood-Risk
Management Options:
Urban Flood-Risk LevelsL M H
Conservation Areas Flood-Risk Levels L M H
Lake Okechobee Water Level14.5’ 16.5’ 17.5’
release
Lock
Release to L-8, L-10
A.
Release water toC-43 and C-44 St. Lucie Canal; Caloosahatchee Canal
B.
Release water toL-8 and L-10 STA 1-W and 1-E; WCA 1 (Lox. NWR)
Decision Impacts:
Preview Preview
B.
Miami-Dade Impact:Flood-risk reduced
Loxahatchee NWR/Everglades Impact:Apple snail population andwaterfowl nesting inundated
High Flood-Risk
Water reaches STA 1-W and 1-E
Water released to WCA 1, (Lox)
Water reaches WCA 2, WCA 3
Water reaches Everglades
Apple Snail pop. disturbed
Scenario 2Conditions:Drought SeasonSFWMD Phase IV Drought “Critical”Loxahatchee NWR and Everglades National Park need water
SFWMD Drought Protocol: Water Restrictions Stages I II III IV
Flow RateNone Minimum Adequate
Severe Drought
timeline
Release water to L-8, L-10
Water reaches STA 1-W and 1-E
Water released to WCA 1, (Lox)
Water reaches WCA 2, WCA 3
Water reaches Everglades
Management Options:
A.
Miami-Dade Impact:Water restrictions remain Phase IV
Loxahatchee NWR/Everglades Impact:Minimum flows received, still dry
A.
Release min. flows to L-8, L-10, STA 1-W and 1-E, WCA 1 Loxahatchee NWR; Everglades
B.
Release water toL-15 and L-18 Miami-Dade and West Palm Beach
Decision Impacts:
Preview Preview
Scenario 2Conditions:Drought SeasonSFWMD Phase IV Drought “Critical”Loxahatchee NWR and Everglades National Park need water
SFWMD Drought Protocol: Water Restrictions Stages I II III IV
Flow RateNone Minimum Adequate
Drought severe
Release water to L-15, L-18
Water reaches Miami-Dade County line
Water restrictions reduced Phase III
Management Options:
A.
Release min. flows to L-8, L-10, STA 1-W and 1-E, WCA 1 Loxahatchee NWR; Everglades
B.
Release water toL-15 and L-18 Miami-Dade and West Palm Beach
Decision Impacts:
Preview Preview
B.
Miami-Dade Impact:Water restrictions reduced to Phase III
Loxahatchee NWR/Everglades Impact:Apple snail population failsMandatory minimum flows not met
Min. flows to Everglades not met
Conclusions
Spatiotemporal Scenario Management Needed– Typical scenario study generates 100+ layers– Logical dependencies important to preserve
Sharing is Nice– Single-application solutions inadequate– Many raw data ‘standards’ to pick from– Higher-level aggregations desirable
Future Work
Telluride Prototype– Go live this summer– Kept simple
Time slices only Interface exposes dependencies as hierarchies Back-end ScenarioXML drives interface
Everview2– To be developed next academic year