Research/Terra/ 333321
Task evidence / spatial-analysis

Towns in deep snow

PassComputational taskUnpublished draft
Download evidence JSON ↓

The question

333321
How many US towns with population over 5000 are located in areas with snow cover exceeding 3 feet?
Exact submitted task and declared adaptations
How many US towns with population over 5000 are located in areas with snow cover exceeding 3 feet?

Task conventions: Use the source's 2010 population field and the frozen 2024-09-30 through 2025-05-20 snowfall raster, measured in inches. Both thresholds are strictly greater than. Count source records, retaining benchmark_row_id; repeated GNIS IDs are not a deduplication instruction. Sample the pixel containing each point. Report the count supported by valid snowfall cells, and separately the number of population-eligible records whose snowfall is unknown (outside coverage or NoData). Do not claim complete nationwide coverage.



Compute the answer using only the supplied immutable fixtures. Save the selected features with their benchmark_row_id and original geometry as an inspectable data artifact. In your accepted final answer include one JSON code block with count (integer), unknown_count (integer), coverage_note (string), and selection (an object with collectionId, itemId, assetKey for that artifact). Maps are optional. Do not request clarification: the task conventions are fixed. Do not use live substitutes, shrink the study question, or use external benchmark answers.

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": "US cities and towns, 2014",
    "edition": "2014; pop_2010 is 2010 population",
    "units": {
      "pop_2010": "people"
    },
    "collectionId": "blue-generated--[resource id withheld]",
    "itemId": "[resource id withheld]",
    "assetKey": "data"
  },
  {
    "name": "US snowfall, 2024\u201325 frozen season",
    "edition": "2024-09-30 to 2025-05-20",
    "units": {
      "band1": "inches"
    },
    "collectionId": "blue-generated--[resource id withheld]",
    "itemId": "[resource id withheld]",
    "assetKey": "data"
  }
]

Outcome & verification

Independent artifact and delivery checks passed.

Duration
16m 56s
Recorded Blue tool calls
40
Total tokens
1,738,272
Model cost
Not recorded
Application revision
d50497ea9084f29c91b05406688f87035df98d8a
Release
terra-geobenchx-v1

Recorded final answer

Using the supplied 2014 towns fixture and the frozen 2024-09-30 to 2025-05-20 snowfall raster, 460 town records meet both thresholds. Another 236 population-eligible records have unknown snowfall because the sampled raster value is null, so this is not a complete nationwide count. The selected records artifact is attached for inspection. ### Limitations - Supported count uses only valid sampled snowfall cells from the supplied raster; population-eligible towns with null snowfall samples remain unknown and are reported separately. - This filter does not establish snowfall coverage or snowfall threshold compliance by itself. - The supported count is limited to valid sampled raster cells. Null samples remain unknown because they are outside coverage or NoData.

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
460
Reported count
460
Computation verified
Yes
Answer fulfilled
Yes
Full grading and rubric record
{
  "expectedCount": 460,
  "actualCount": 460,
  "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

Using only the supplied immutable fixtures, does filtering towns by pop_2010 > 5000, sampling the frozen snowfall raster at each point, and splitting the sampled records into snowfall > 36 inches versus unknown null samples produce the required selected and unknown town sets nationwide?

assess_trial · completed · assessment: sufficient

The nationwide fixed-input trial answered the method question. Filtering the supplied towns fixture with pop_2010 > 5000 produced 5,919 eligible source records. Sampling the supplied snowfall raster added a snow_inches field while preserving benchmark_row_id and point geometry. Filtering sampled rows with valid snow_inches > 36 produced 460 selected records, and filtering sampled rows where snow_inches is null produced 236 eligible records with unknown snowfall. The selected set retains source records without deduplication, and the unknown set captures the required outside-coverage or NoData outcomes as null samples.

assess_result · completed · assessment: sufficient

Using only the supplied immutable fixtures, the saved workflow counted 460 source town records with pop_2010 > 5000 and sampled snowfall > 36 inches, and it found 236 population-eligible source records whose snowfall sample is unknown because the sampled raster value is null. The selected artifact preserves benchmark_row_id, original point geometry, pop_2010, and snow_inches for inspection. This is a supported count only for valid sampled snowfall cells from the supplied frozen-season raster, not a complete nationwide coverage claim.

Recorded workflow

  1. 01

    Selected towns with snowfall over 36 inches

    Recorded output · succeeded

  2. 02

    Population-eligible towns with unknown snowfall

    Recorded output · succeeded

  3. 03

    Population-eligible towns

    Recorded vector-filter · succeeded

  4. 04

    Sample snowfall at eligible towns

    Recorded raster-sample · succeeded

  5. 05

    Selected towns with snowfall over 36 inches

    Recorded vector-filter · succeeded

  6. 06

    Supplied snowfall fixture

    Recorded source · succeeded

  7. 07

    Supplied towns fixture

    Recorded source · succeeded

  8. 08

    Eligible towns with unknown snowfall

    Recorded vector-filter · succeeded

  9. 09

    Population-eligible towns

    Recorded vector-filter · succeeded

  10. 10

    Sample snowfall at eligible towns

    Recorded raster-sample · succeeded

  11. 11

    Selected towns with snowfall over 36 inches

    Recorded vector-filter · succeeded

  12. 12

    Supplied snowfall fixture

    Recorded source · succeeded

  13. 13

    Supplied towns fixture

    Recorded source · succeeded

  14. 14

    Population-eligible towns

    Recorded output · succeeded

  15. 15

    Sample snowfall at eligible towns

    Recorded output · succeeded

  16. 16

    Selected towns with snowfall over 36 inches

    Recorded output · succeeded

  17. 17

    Eligible towns with unknown snowfall

    Recorded output · succeeded

  18. 18

    Eligible towns with unknown snowfall

    Recorded vector-filter · 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 and the fixed input files first, then I’ll build the smallest valid workflow to count eligible towns and keep an inspectable selection artifact.

  2. get_analysis

    Recorded tool call · completed

  3. get_collection

    Recorded tool call · completed

  4. get_collection

    Recorded tool call · completed

  5. list_items

    Recorded tool call · completed

  6. get_analysis

    Recorded tool call · completed

  7. list_items

    Recorded tool call · completed

  8. Progress update

    I found the fixed vector and raster fixtures and their declared extents. Next I’m checking the actual item metadata/fields so I can test the exact population and snowfall columns without guessing processor inputs.

  9. list_processors

    Recorded tool call · completed

  10. get_tool_help

    Recorded tool call · completed

  11. list_processors

    Recorded tool call · completed

  12. list_processors

    Recorded tool call · completed

  13. describe_processors

    Recorded tool call · completed

  14. describe_processors

    Recorded tool call · completed

  15. Progress update

    I’ve narrowed the method to three simple steps: filter towns by `pop_2010 > 5000`, sample the snowfall raster at each point, then split the sampled towns into “snow > 36” and “snow unknown”. I’m reading the exact processor contracts now so I don’t guess how null/NoData sampling is represented.

  16. update_analysis_brief

    Recorded tool call · completed

  17. get_tool_help

    Recorded tool call · completed

  18. get_tool_help

    Recorded tool call · completed

  19. get_tool_help

    Recorded tool call · completed

  20. Progress update

    I’ve got the exact full-scope method. I’m testing it privately once before saving the public workflow so I can confirm the sampled snowfall field and null handling on the real nationwide inputs rather than guessing.

  21. run_trial

    Recorded tool call · completed

  22. get_trial_report

    Recorded tool call · completed

  23. Progress update

    The private full-scope test worked: it found 5,919 population-eligible town records, added a `snow_inches` sample field, and separated 460 supported selected towns from 236 eligible towns with unknown snowfall. I’m inspecting that test result and turning the same tested method into the final saved workflow now.

  24. get_tool_help

    Recorded tool call · completed

  25. Progress update

    The trial confirmed the exact field behavior I needed: the sampled field is `snow_inches`, selected rows all have valid `snow_inches > 36`, and unknown rows are null samples. I’m saving the tested nationwide method as the final workflow so I can inspect the final artifacts and attach the answer cleanly.

  26. get_tool_help

    Recorded tool call · completed

  27. get_tool_help

    Recorded tool call · completed

  28. get_tool_help

    Recorded tool call · completed

  29. get_tool_help

    Recorded tool call · completed

  30. get_tool_help

    Recorded tool call · completed

  31. get_tool_help

    Recorded tool call · completed

  32. assess_trial

    Recorded tool call · completed

  33. propose_workflow

    Recorded tool call · completed

  34. Progress update

    The final workflow is validated and matches the successful nationwide trial exactly. I’m executing it now so I can attach the final selected-features artifact and the machine-readable answer from the saved workflow outputs.

  35. execute_workflow

    Recorded tool call · completed

  36. inspect_workflow_results

    Recorded tool call · completed

  37. inspect_artifact

    Recorded tool call · completed

  38. inspect_artifact

    Recorded tool call · completed

  39. inspect_artifact

    Recorded tool call · completed

  40. Progress update

    I’ve already got the final counts from the saved workflow. I’m refreshing the bounded inspections one more time to pull the immutable receipts for the selected rows, the unknown rows, and the sampled towns table before I record the final answer.

  41. inspect_artifact

    Recorded tool call · completed

  42. inspect_artifact

    Recorded tool call · completed

  43. inspect_artifact

    Recorded tool call · completed

  44. get_analysis

    Recorded tool call · completed

  45. get_tool_help

    Recorded tool call · completed

  46. Progress update

    I’ve confirmed the final saved outputs themselves: 460 selected rows, 236 unknown rows, and the sampled table shows 236 null snowfall values among 5,919 population-eligible rows. I’m recording the final result now with the selected-features artifact attached.

  47. Progress update

    I’ve verified the final saved artifacts now, so I’m clearing the stale “not yet run” notes before filing the result. Then I’ll give the short answer that matches the attached selection.

  48. update_analysis_brief

    Recorded tool call · completed

  49. revise_workflow

    Recorded tool call · completed

  50. Progress update

    I refreshed the brief notes after the outputs were confirmed. I’m revalidating the saved workflow reference once so the retained planning record stays in sync with the finished result, then I’ll file the final assessment.

  51. assess_result

    Recorded tool call · completed

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