{
  "walk_nav": {
    "aria_label": "Walkthrough",
    "tab_question": "1. Your question",
    "tab_how_sure": "2. How sure is each?",
    "tab_why": "3. Why they disagree",
    "tab_answer": "4. The answer",
    "back": "Back",
    "evidence": "What is this based on?"
  },
  "walk_steps": {
    "question_eyebrow": "Your question",
    "question_title": "Is there iron oxide at Cuprite, Nevada?",
    "question_body": "Iron oxide absorbs blue light and near-infrared light around 880 nm; the gold band marks that signature. Two satellites measured the same ground. Sentinel-2A follows the signature closely. Landsat 9, as delivered, effectively measures wider bands, shifted from what each is intended to measure, so it smears the signature out. Your question needs three bands from each.",
    "question_next": "How sure is each?",
    "how_sure_eyebrow": "How sure is each?",
    "how_sure_title": "How sure is each satellite?",
    "how_sure_body": "Compare both at 865 nm, where iron oxide reflects a known share of sunlight. Each satellite reports one precise number, but many factors, and the ways they interact, come between that number and the ground. So we show, as a curve, how likely each value is to match the ground truth: narrow means sure, wide means unsure. Before trusting either, we need to know why they disagree.",
    "how_sure_next": "Why do they disagree?",
    "haze_eyebrow": "Why they disagree: example 1 of 3",
    "haze_title": "Factor out the haze in the air",
    "haze_body": "RefCal weighs a large array of factors about the sensor, the atmosphere and the input data, and how they interact. Here are three examples, one for each way a factor acts. Haze left a long bright tail on Landsat 9's curve. RefCal knows how Landsat 9 responds to haze and water vapour from many well-known sites; factoring it out pulls the tail in.",
    "haze_next": "Next: the angle of the sun",
    "sun_eyebrow": "Why they disagree: example 2 of 3",
    "sun_title": "Factor out the angle of the sun",
    "sun_body": "Some factors move the centre of a curve. The sun was lower when Landsat 9 passed over than when Sentinel-2A did; its angle changes how the ground is lit and the light's path through the air, and interacts with the haze. Factoring it out, with evidence from calibration sites, shifts Landsat 9's curve and tightens the bands it effectively measures.",
    "sun_next": "Next: the sensor itself",
    "drift_eyebrow": "Why they disagree: example 3 of 3",
    "drift_title": "Factor out drift in the sensor itself",
    "drift_body": "Some factors narrow a curve around the value it already has. Every sensor ages and drifts. RefCal tracks this sensor's drift through repeated measurements of reference sites whose brightness is known, such as the RadCalNet network, and even the Moon. That evidence makes the Landsat 9 reading surer without moving it.",
    "drift_next": "See the answer",
    "answer_eyebrow": "The answer",
    "answer_title": "Likely iron oxide here",
    "answer_body": "The two readings still differ, and that difference is information: only the narrow purple range fits both, and it sits inside the iron oxide range. The purple line is its most likely value. Behind it sit many more factors than these three: calibration, matching between instruments and wavelengths, the atmosphere, and the quality of each input."
  },
  "walk_fig": {
    "sentinel": "Sentinel-2A",
    "landsat": "Landsat 9",
    "spec_caption": "Fig. 1 / Light missing, by wavelength",
    "spec_signature": "iron oxide signature",
    "spec_band_legend": "band: thick = wavelengths it is intended to measure, bracket = what it effectively measures",
    "spec_aria": "Share of light missing by wavelength for both satellites against the iron oxide signature; a bar through each reading shows the wavelengths its band is intended to measure and what it effectively measures",
    "spec_hover": "{satellite}, band intended to measure {from} to {to} nm; effectively measures {eff_from} to {eff_to} nm. Light missing: {missing} (95% range {lo} to {hi}).",
    "bell_caption": "Fig. 2 / Likely value at 865 nm",
    "bell_both": "what both support",
    "bell_bars": "bars: 95% range",
    "bell_aria": "How likely each share of sunlight reflected at 865 nm is, per satellite, against the iron oxide range",
    "bell_box": "Iron oxide range",
    "bell_axis": "Share of sunlight reflected at 865 nm"
  },
  "walk_result": {
    "likely": "likely {lo} to {hi}",
    "reads": "reads {now}, was {was}",
    "likely_was": "likely {lo} to {hi}, was {was_lo} to {was_hi}",
    "answer_key": "Both readings support",
    "answer_inside": "{lo} to {hi}, inside the iron oxide range",
    "answer_not_inside": "{lo} to {hi}, not inside the iron oxide range"
  },
  "walk_evidence": {
    "title": "What each factor is based on",
    "lead": "RefCal weighs many more factors than these three examples. Each rests on measurements you can check. Here is what these three rest on.",
    "back": "Back to the factors",
    "haze_name": "Haze in the air",
    "haze_basis": "Landsat 9's readings over many sites whose brightness is well measured, such as Railroad Valley in Nevada, across many levels of haze and water vapour.",
    "haze_volume": "1,240 matched looks",
    "haze_effect": "Pulled in the bright tail: the range now ends at {now}, was {was}",
    "sun_name": "Angle of the sun",
    "sun_basis": "The sun's position at the exact time of each image, and how it interacts with the air measured that day.",
    "sun_volume": "Every image",
    "sun_effect": "Moved the centre by {move}",
    "drift_name": "The sensor's own drift",
    "drift_basis": "Repeated measurements of RadCalNet reference sites and of the Moon, whose brightness is known and steady.",
    "drift_volume": "Monthly",
    "drift_effect": "Narrowed the range to {now} wide, was {was}"
  },
  "walk_gated": {
    "title": "See the numbers for your own site",
    "body": "Anyone can follow how RefCal reaches an answer. The numbers for a real site come with a full demonstration account, which we set up for you.",
    "col_reading": "Reading",
    "col_from": "Likely from",
    "col_to": "Likely to",
    "row_sentinel": "Sentinel-2A at 865 nm",
    "row_landsat": "Landsat 9 at 865 nm, factors removed",
    "row_both": "Both together",
    "cta_title": "Get the numbers for your site",
    "cta_body": "Tell us the site and the question. We set up the account.",
    "cta_button": "Contact SpectraWorks",
    "back": "Back to the walkthrough"
  }
}