Research/Terra/ 480358
Task evidence / contour-map

Make contour lines of population density in flood-affected areas of Bangladesh.

PassComputational taskUnpublished draft
Download evidence JSON ↓

The question

480358
Make contour lines of population density in flood-affected areas of Bangladesh.
Exact submitted task and declared adaptations
Make contour lines of population density in flood-affected areas of Bangladesh.

Task conventions: Use the frozen 2018 Bangladesh population raster and supplied event flood_bangladesh. Population source values are people/km2. Keep its entire original grid; no population resampling. Sample the original flood raster at each original population-cell centre by containing pixel (nearest alignment); no max/bilinear interpolation or inferred flooded fractions. GFD bands are 1 flooded (0/1), 2 duration in days, 3 clear-view count, 4 clear-view fraction, 5 permanent water (0/1). Observe a cell only if population is finite/unmasked, bands 1,3,5 are finite/unmasked, clear views >0, and permanent water=0. Observed band1=1 is flooded; observed band1=0 is non-flooded. Everything else is unknown/excluded, never non-flooded or zero population. Calculate original full geographic-cell WGS84 ellipsoidal meridian/parallel area in km2; density is counts/area and counts are density*area as appropriate. Sum original/derived population over flooded cells. For the density comparison use group population divided by group physical area, not an unweighted mean of densities. This explicitly defines affected as people in observed flooded cell centres, not proven personal impacts. The event covers only part of the country/month: report the observed-footprint result, never an exhaustive national total. The supplied Bangladesh event's footprint includes northern Bangladesh despite its Tibetan event label; inspect actual coverage. Permanent water, cloud gaps and unobserved regions do not establish absence of flooding. No current source substitutions. Internal benchmark only. For this contour question retain original population-density values only at observed flooded cell centres; observed dry cells, permanent water and unknown coverage must all be NoData, not zero. Then Use band 1 of the frozen bangladesh_density raster at the original grid without resampling, smoothing or clipping. Draw the explicit contour levels [100, 500, 1000, 5000, 10000] in people/km2. These levels are a disclosed evaluation convention, not a requested interval. Use piecewise-linear marching-squares isolines through pixel-center values, low-valued connectivity at ambiguous saddles. Respect the native mask, NoData and nonfinite cells; do not bridge holes or extrapolate at the outside edge. Apply any source scale and offset. NoData means unknown, never zero. Preserve source coverage; levels outside the observed range may have no line. Do not substitute a current raster. Count nonempty requested contour LEVELS, not polyline fragments. The supplied Bangladesh raster is verified people/km2, not counts; do not divide it by area again. 



Deliver an inspectable vector contour artifact and add it to the map with a level/units legend. End with one fenced JSON object containing: count (number of nonempty requested levels), unknown_count (number of masked or nonfinite source pixels), coverage_note, selection: {collectionId,itemId,assetKey}, level_field, feature_count (actual contour feature rows), map_layer_id. Explain the source season/year, units, missing coverage, and visual relationship where an overlay is requested.

Delivery format: provide the answer object with all fields specified above as final_response on assess_result, alongside the inspected final artifact_refs. This replaces the JSON-code-block formatting requirement above. Blue attaches your explicit selection to the accepted final answer. Finish with a concise ordinary-language answer agreeing with that selected result; do not duplicate the JSON in chat.

Supplied immutable inputs:
[
  {
    "name": "Bangladesh population density, WorldPop 2018",
    "edition": "2018 UN-adjusted 1 km density; exact bytes verified against WorldPop product 45189, DOI WP00675",
    "units": {
      "band1": "people/km\u00b2"
    },
    "collectionId": "blue-generated--[resource id withheld]",
    "itemId": "[resource id withheld]",
    "assetKey": "data"
  },
  {
    "name": "GFD observed flood 4665, 2018-08-02 to 2018-08-10",
    "edition": "Original five-band GFD v1 benchmark snapshot, not a current flood map; benchmark-only use",
    "units": {
      "band1": "binary flooded flag",
      "band2": "days",
      "band3": "observations",
      "band4": "fraction",
      "band5": "binary permanent-water flag"
    },
    "collectionId": "blue-generated--[resource id withheld]",
    "itemId": "[resource id withheld]",
    "assetKey": "data"
  }
]

Outcome & verification

Independent artifact and delivery checks passed.

Duration
24m 24s
Recorded Blue tool calls
63
Total tokens
4,739,356
Model cost
Not recorded
Application revision
d50497ea9084f29c91b05406688f87035df98d8a
Release
terra-geobenchx-v1

Recorded final answer

Done — I added **Flood-affected population density contours** to the map. It uses the frozen **WorldPop 2018 Bangladesh density** raster in **people/km²** and the supplied **GFD event for 2018-08-02 to 2018-08-10**. All five requested contour levels are present. On the map, the lines stay within the **observed flooded footprint**, including **northern Bangladesh**. They do **not** continue across dry cells, permanent water, cloud gaps, or other unobserved areas, which remain blank. This is an **observed-footprint result**, not an exhaustive national flood total. ### Limitations - This result covers only the overlap of the supplied 2018 Bangladesh density raster and the observed 2018-08-02 to 2018-08-10 GFD footprint. - Cloud gaps, permanent water, and any unobserved cells remain unknown or excluded and are not treated as dry or zero population. - The density source is the fixed 2018 WorldPop benchmark raster, not a current population surface. - No separate Bangladesh boundary source is bound here, so the executable extent is the supplied Bangladesh raster extent rather than an independently retrieved national polygon. - Observed-footprint only: the event covers part of Bangladesh and part of August 2018, so this is not an exhaustive national flood total. - Population is from the frozen WorldPop 2018 UN-adjusted density raster, not a current population surface. - Contours represent people/km² only at observed flooded cell centres; dry cells, permanent water, cloud gaps, and all unobserved areas remain excluded or unknown. - This is an observed flooded cell-centre population screen, not proof of personal impacts. - The executable extent follows the supplied Bangladesh raster extent rather than an independently retrieved national boundary polygon. - This is the fixed 2018 benchmark density surface, not a current population map. - Only cells with finite population, finite flood bands 1, 3, and 5, clear views greater than zero, and permanent water equal to zero are observed. - Cloud gaps, permanent water, and unobserved cells remain unknown or excluded rather than dry. - The executable study area is the supplied Bangladesh density raster extent because no separate national boundary source is bound here. - The observed event footprint covers only part of the country and month, though the tested footprint does reach northern Bangladesh within the supplied raster extent. - Contours are drawn only where the masked flooded-density raster has valid values; holes and outside edges are not bridged or extrapolated. - A requested level would be absent if it has no crossing in the observed flooded density range.

Independent checks

These checks are separate from the agent's own assessment. A successful job or an assertion of success is not enough to pass.

Expected count
5
Reported count
5
Computation verified
Yes
Answer fulfilled
Yes
Full grading and rubric record
{
  "expectedCount": 5,
  "actualCount": 5,
  "expectedMetrics": null,
  "actualMetrics": null,
  "computationCorrect": true,
  "answerFulfilled": true,
  "adjudication": null,
  "qualification": null,
  "reasons": []
}

Recorded investigation findings

The agent's reported hypotheses and assessments, retained as evidence of its process—not independent proof that the answer is correct. Failed calls retain their requested verdict, not an accepted assessment.

run_trial · completed

Does the no-resampling Bangladesh-wide method produce a flooded-only density raster, finite observed-footprint population totals, and contour lines only at the requested levels from the supplied 2018 density raster and supplied 2018-08-02 to 2018-08-10 GFD event?

assess_trial · completed · assessment: insufficient

The Bangladesh-wide no-resampling trial kept the supplied 2018 density grid intact, sampled the GFD event bands onto that grid with nearest alignment, and produced a masked flooded-density raster with 12,177 valid flooded cells and 394,775 masked cells. The contour output contained all five requested levels with a level field in people/km² and 710 total line features. The spatial preview shows observed flooded density and contours extending into northern Bangladesh within the supplied Bangladesh raster extent, which matches the user's warning to inspect actual event coverage rather than its label. The observed-footprint flooded population total was finite at about 9.67 million people over about 9,437.44 km² of observed flooded cell area.

run_trial · completed

Do the corrected support outputs keep unknown and excluded cells as NoData while preserving the observed-footprint flooded population and flooded area totals for the Bangladesh-wide no-resampling method?

assess_trial · completed · assessment: sufficient

The corrected support outputs now keep unknown and excluded cells as NoData while preserving the Bangladesh-wide observed-footprint totals. The corrected observed-flood classification has 37,577 valid observed cells and 369,375 masked cells, and its map-algebra inspection shows validOutputWithMissingInputCount = 0, so missing flood inputs no longer turn into valid dry values. The corrected flooded population summary still sums to 9,671,176.246214867 people over 12,177 flooded cells, and the corrected flooded area summary still sums to 9,437.438377141953 km² over the same 12,177 flooded cells. This confirms that only the outside-flood encoding changed; the flooded-only totals did not.

assess_result · completed · assessment: sufficient

The published contour artifact contains 710 contour features across all five requested levels and is already on the map as Flood-affected population density contours. Its source flooded-density surface retains 12,177 observed flooded population cells and masks 394,775 dry, permanent-water, or unknown cells. The observed-footprint summaries are 9,671,176.246214867 people over 9,437.438377141953 km² for the supplied 2018-08-02 to 2018-08-10 GFD event over the frozen 2018 Bangladesh WorldPop density raster. The contour preview and earlier full-area trial both show the observed footprint extending into northern Bangladesh, while contours stay confined to observed flooded areas rather than crossing dry or unknown gaps.

Recorded workflow

  1. 01

    Contour rows by level

    Recorded table-group-statistics · succeeded

  2. 02

    Requested density contours

    Recorded raster-contours · succeeded

  3. 03

    Flood-affected population density contours

    Recorded output · succeeded

  4. 04

    Contour level counts

    Recorded output · succeeded

  5. 05

    Flooded density coverage summary

    Recorded output · succeeded

  6. 06

    Observed flooded population summary

    Recorded output · succeeded

  7. 07

    Observed flooded area summary

    Recorded output · succeeded

  8. 08

    Flood band 1

    Recorded raster-extract-band · succeeded

  9. 09

    Flood flag on population grid

    Recorded raster-align · succeeded

  10. 10

    Flood band 3

    Recorded raster-extract-band · succeeded

  11. 11

    Clear-view count on population grid

    Recorded raster-align · succeeded

  12. 12

    Flood band 5

    Recorded raster-extract-band · succeeded

  13. 13

    Permanent-water flag on population grid

    Recorded raster-align · succeeded

  14. 14

    Flooded observed area

    Recorded raster-map-algebra · succeeded

  15. 15

    Flooded area summary

    Recorded raster-statistics · succeeded

  16. 16

    Flooded population counts

    Recorded raster-map-algebra · succeeded

  17. 17

    Flooded population summary

    Recorded raster-statistics · succeeded

  18. 18

    Observed flood classification

    Recorded raster-map-algebra · skipped

  19. 19

    Supplied GFD event

    Recorded source · succeeded

  20. 20

    Flooded population density

    Recorded raster-map-algebra · succeeded

  21. 21

    Flooded density stats

    Recorded raster-statistics · succeeded

  22. 22

    Population cell area

    Recorded raster-cell-area · succeeded

  23. 23

    Population density band

    Recorded raster-extract-band · succeeded

  24. 24

    Population density source stats

    Recorded raster-statistics · skipped

  25. 25

    Supplied Bangladesh density

    Recorded source · succeeded

  26. 26

    Flood band 1

    Recorded raster-extract-band · succeeded

  27. 27

    Flood flag on population grid

    Recorded raster-align · succeeded

  28. 28

    Flood band 3

    Recorded raster-extract-band · succeeded

  29. 29

    Clear-view count on population grid

    Recorded raster-align · succeeded

  30. 30

    Flood band 5

    Recorded raster-extract-band · succeeded

  31. 31

    Permanent-water flag on population grid

    Recorded raster-align · succeeded

  32. 32

    Corrected flooded observed area

    Recorded raster-map-algebra · succeeded

  33. 33

    Corrected flooded area summary

    Recorded raster-statistics · succeeded

  34. 34

    Corrected flooded population counts

    Recorded raster-map-algebra · succeeded

  35. 35

    Corrected flooded population summary

    Recorded raster-statistics · succeeded

  36. 36

    Corrected observed flood classification

    Recorded raster-map-algebra · succeeded

  37. 37

    Supplied GFD event

    Recorded source · succeeded

  38. 38

    Population cell area

    Recorded raster-cell-area · succeeded

  39. 39

    Population density band

    Recorded raster-extract-band · succeeded

  40. 40

    Supplied Bangladesh density

    Recorded source · succeeded

  41. 41

    Corrected observed flood classification

    Recorded output · succeeded

  42. 42

    Corrected flooded population summary

    Recorded output · succeeded

  43. 43

    Corrected flooded area summary

    Recorded output · succeeded

  44. 44

    Contour rows by level

    Recorded table-group-statistics · succeeded

  45. 45

    Requested density contours

    Recorded raster-contours · succeeded

  46. 46

    Flood band 1

    Recorded raster-extract-band · succeeded

  47. 47

    Flood flag on population grid

    Recorded raster-align · succeeded

  48. 48

    Flood band 3

    Recorded raster-extract-band · succeeded

  49. 49

    Clear-view count on population grid

    Recorded raster-align · succeeded

  50. 50

    Flood band 5

    Recorded raster-extract-band · succeeded

  51. 51

    Permanent-water flag on population grid

    Recorded raster-align · succeeded

  52. 52

    Flooded observed area

    Recorded raster-map-algebra · succeeded

  53. 53

    Flooded area summary

    Recorded raster-statistics · succeeded

  54. 54

    Flooded population counts

    Recorded raster-map-algebra · succeeded

  55. 55

    Flooded population summary

    Recorded raster-statistics · succeeded

  56. 56

    Observed flooded cells

    Recorded raster-map-algebra · succeeded

  57. 57

    Supplied GFD event

    Recorded source · succeeded

  58. 58

    Flooded population density

    Recorded raster-map-algebra · succeeded

  59. 59

    Flooded density stats

    Recorded raster-statistics · succeeded

  60. 60

    Population cell area

    Recorded raster-cell-area · succeeded

  61. 61

    Population density band

    Recorded raster-extract-band · succeeded

  62. 62

    Population density source stats

    Recorded raster-statistics · succeeded

  63. 63

    Supplied Bangladesh density

    Recorded source · succeeded

  64. 64

    Population density source stats

    Recorded output · succeeded

  65. 65

    Observed flooded cells

    Recorded output · succeeded

  66. 66

    Flooded population density

    Recorded output · succeeded

  67. 67

    Flooded density stats

    Recorded output · succeeded

  68. 68

    Flooded population summary

    Recorded output · succeeded

  69. 69

    Flooded area summary

    Recorded output · succeeded

  70. 70

    Requested density contours

    Recorded output · succeeded

  71. 71

    Contour rows by level

    Recorded output · succeeded

Activity

Recorded actions

Recorded observable actions only, not private reasoning. Raw payloads, geometry, private links and credentials are omitted; full evidence is retained privately. Activity/workflow lists bounded at 500 entries.

  1. Progress update

    I’m checking the saved analysis context first, then I’ll inspect the two supplied rasters and the relevant raster/vector processors.

  2. get_analysis

    Recorded tool call · completed

  3. get_map_context

    Recorded tool call · completed

  4. get_analysis

    Recorded tool call · completed

  5. get_collection

    Recorded tool call · completed

  6. get_collection

    Recorded tool call · completed

  7. Progress update

    I found no saved brief yet, so I’m inspecting the two supplied rasters now. After that I’ll save the analysis brief and test the flood-mask + contour method on a small slice before scaling to the whole footprint.

  8. inspect_artifact

    Recorded tool call · failed

  9. inspect_artifact

    Recorded tool call · failed

  10. Progress update

    I’ve confirmed the immutable inputs and their extents. Next I’m finding the exact raster and contour processors so I can build the method against the original grid instead of guessing tool names.

  11. list_processors

    Recorded tool call · completed

  12. list_processors

    Recorded tool call · completed

  13. list_processors

    Recorded tool call · completed

  14. get_tool_help

    Recorded tool call · completed

  15. describe_processors

    Recorded tool call · completed

  16. describe_processors

    Recorded tool call · completed

  17. Progress update

    I’ve found the key processors: nearest grid alignment, band extraction, map algebra, cell-area, full raster stats, and marching-squares contours. I’m checking for a Bangladesh boundary now so the study area is anchored to an actual region rather than a remembered bbox.

  18. search_catalog

    Recorded tool call · completed

  19. search_catalog

    Recorded tool call · completed

  20. search_catalog

    Recorded tool call · completed

  21. update_analysis_brief

    Recorded tool call · completed

  22. get_tool_help

    Recorded tool call · completed

  23. describe_processors

    Recorded tool call · completed

  24. list_processors

    Recorded tool call · completed

  25. describe_processors

    Recorded tool call · completed

  26. describe_processors

    Recorded tool call · completed

  27. describe_processors

    Recorded tool call · completed

  28. describe_processors

    Recorded tool call · completed

  29. describe_processors

    Recorded tool call · completed

  30. describe_processors

    Recorded tool call · completed

  31. get_tool_help

    Recorded tool call · completed

  32. get_tool_help

    Recorded tool call · completed

  33. get_tool_help

    Recorded tool call · completed

  34. get_tool_help

    Recorded tool call · completed

  35. get_tool_help

    Recorded tool call · completed

  36. get_tool_help

    Recorded tool call · completed

  37. get_tool_help

    Recorded tool call · completed

  38. Progress update

    I’ve got a workable full-country method to test privately: extract the fixed density band, nearest-align the flood observation bands to that grid, build the observed-flood mask, derive the masked density raster and flooded-population totals, then contour only the requested levels. I’m running that now so I can inspect the actual outputs before I save the public draft.

  39. run_trial

    Recorded tool call · completed

  40. Progress update

    The private test finished. It produced a flooded-only density raster and contour lines at all five requested levels. I’m checking the spatial previews now, then I’ll lock in the final workflow with the remaining mask/summary cleanup so unknown cells stay excluded rather than looking like valid zeroes.

  41. get_trial_report

    Recorded tool call · completed

  42. Progress update

    The test answered the core method question, but one support layer still treats unknown flood input as a valid zero. I’m recording that as a work-in-progress finding, then I’ll save the corrected production workflow so the published artifacts keep excluded cells as NoData throughout.

  43. assess_trial

    Recorded tool call · completed

  44. get_tool_help

    Recorded tool call · completed

  45. get_tool_help

    Recorded tool call · completed

  46. get_tool_help

    Recorded tool call · completed

  47. Progress update

    I’ve got the corrected production method: the contours stay exactly as tested, while the support mask and helper rasters now keep excluded cells as NoData instead of zero. I’m saving that full workflow draft with the contour map plus the summary tables needed for the final answer.

  48. propose_workflow

    Recorded tool call · failed

  49. Progress update

    Blue flagged one contract field as ambiguous, not a data problem. I’m correcting that binding now so the saved workflow points explicitly to the contour output that uses the flood observation rule.

  50. propose_workflow

    Recorded tool call · failed

  51. Progress update

    I’m trimming the contract to the processors that directly feed the contour result. The summary tables still stay in the workflow, but the contract needs the shortest explicit path to the final map output.

  52. propose_workflow

    Recorded tool call · completed

  53. get_analysis

    Recorded tool call · completed

  54. Progress update

    The workflow draft is scientifically ready, but Blue still wants the earlier adverse finding tied explicitly to this corrected proposal. I’m linking that finding to the saved revision now so the draft becomes runnable.

  55. assess_plan

    Recorded tool call · failed

  56. Progress update

    I’m running one focused correction test now. It only checks the changed support outputs: the observed flood mask should keep unknown cells as NoData, and the flooded population/area totals should stay the same after that cleanup.

  57. run_trial

    Recorded tool call · completed

  58. Progress update

    The correction run finished too. It confirms the cleaned-up support outputs now keep unknown cells missing and preserve the same observed-footprint totals. I’m recording that, then I’ll clear the saved workflow finding and launch the final run.

  59. get_trial_report

    Recorded tool call · completed

  60. assess_trial

    Recorded tool call · completed

  61. Progress update

    The correction is now assessed as sufficient. I’m applying it to the saved workflow finding so the proposal can run as the final Bangladesh contour job.

  62. assess_plan

    Recorded tool call · completed

  63. execute_workflow

    Recorded tool call · completed

  64. Progress update

    The workflow is now cleared to run. I’m starting the final production run and will inspect the exact contour artifact, summary tables, and map binding before I finish.

  65. Progress update

    The final run completed in the background. I’m inspecting the exact outputs now so I can confirm the contour rows, the nonempty levels, the masked-pixel count, and the map layer binding from the actual final artifacts.

  66. inspect_workflow_results

    Recorded tool call · completed

  67. Progress update

    I’m resuming from the completed final run. Next I’m reading the exact output artifacts and then I’ll bind the contour layer to the map so the final answer references the real layer and item.

  68. inspect_workflow_results

    Recorded tool call · completed

  69. Progress update

    I have the final output identities. I’m pulling the remaining final deliverables now so I can confirm the contour artifact itself, the masked-pixel count, and the final summary tables from this completed run.

  70. inspect_workflow_results

    Recorded tool call · completed

  71. Progress update

    I’ve confirmed the summary tables. I’m pulling the contour map deliverable itself, plus the final density-coverage and flooded-area deliverables, so the final answer uses the published outputs rather than the earlier trial copies.

  72. inspect_workflow_results

    Recorded tool call · completed

  73. Progress update

    I’ve got the published contour artifact and its map layer. I’m doing one last bounded check on the contour rows and the current map layers so the final answer can reference the exact level counts and live layer ID.

  74. inspect_artifact

    Recorded tool call · completed

  75. inspect_artifact

    Recorded tool call · completed

  76. list_map_layers

    Recorded tool call · completed

  77. Progress update

    I’m just reading back the finished inspection receipts now. After that I can lock the exact contour item, the level counts, and the live map layer into the final result.

  78. inspect_artifact

    Recorded tool call · completed

  79. inspect_artifact

    Recorded tool call · completed

  80. get_tool_help

    Recorded tool call · completed

  81. Progress update

    I’ve verified the published contour item, its five level rows, the 710 feature rows, the 394,775 masked pixels in the contour source, and the live map layer. I’m checking the exact result-assessment syntax now so the final selection is bound cleanly to those inspected outputs.

  82. get_tool_help

    Recorded tool call · completed

  83. get_tool_help

    Recorded tool call · completed

  84. get_tool_help

    Recorded tool call · completed

  85. Progress update

    I have everything needed from the final run: the contour item, the level counts, the masked-pixel count, the observed-footprint totals, and the live layer ID. I’m recording the final result selection now.

  86. assess_result

    Recorded tool call · completed

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