Domain: Humanities and Social Sciences — Geography
Target concept: Cloud types: Cumulus (cotton-like, low-level) and Cirrus (fibrous, high-level)

Video generation prompt: The video shows two layers of clouds: cumulus clouds at a lower altitude on the left and cirrus clouds at a higher altitude on the right. The video highlights the differences in their flow patterns over time.

Evaluation guide:
(i) Target concept: Co-located visual differentiation of cumulus and cirrus clouds as altitude-diagnostic atmospheric features.
Minimum mechanism: Cumulus must originate from buoyant moist air parcels rising into cooler air, producing discrete, dense, thermally driven vertical structures; cirrus must originate from ice nucleation in dry, fast-moving upper tropospheric flow, producing thin, advected, horizontally aligned filaments.
(ii)Storyline: Frame opens on stable sky vista → cumulus clouds emerge/grow vertically on left with convex upward domes and solar-lit upper surfaces → cirrus clouds appear/drift horizontally on right with parallel, feathery strands and consistent directional alignment → both cloud types maintain fixed left/right spatial partition throughout → no morphological cross-contamination (e.g., cirrus does not thicken or lower; cumulus does not stretch horizontally or become fibrous) → viewpoint remains fixed, horizon stable, lighting consistent, enabling direct comparative observation of structural and textural contrast

Manual:
Experimental Procedure
1. Record a 10-second video from a fixed camera position over a wide-angle sky view, keeping the viewpoint stationary while both cloud layers evolve.
2. Ensure cumulus clouds form a distinct cluster on the left half of the frame.
3. Ensure cirrus clouds form a distinct band or patch on the right half of the frame.
Observation of Experimental Phenomena
- Left side: detached, puffy, cauliflower-shaped, bright-topped, vertically developed clouds with soft but defined edges.
- Right side: thin, wispy, fibrous, feathery, translucent strands aligned in parallel, showing no vertical development.
- Clear horizontal separation: no overlap, blending, or occlusion between left and right regions.
Summary of Experimental Principles
Cumulus clouds form at low altitudes (0–2 km) via moist convection, resulting in discrete, dense, vertically grown masses. Cirrus clouds form at high altitudes (6–12 km) from ice crystals advected by upper-level winds, resulting in thin, linear, fibrous structures. Their coexistence in one scene demonstrates atmospheric layering and altitude-dependent cloud physics.

Prompt Grounding rubric:
level_1: No clouds appear in the frame at all, or only one of the two types (cumulus or cirrus) is present with the other entirely missing, or both cloud types overlap in the same vertical column rather than being visible side by side.
level_2: Both cumulus and cirrus appear, but their left/right placement is swapped (cirrus on the left, cumulus on the right), or their textures are swapped (a fibrous strand shape sits on the left while a puffy mass sits on the right), or the two cloud regions blend into a single indistinct mass with no visible boundary.
level_3: A puffy cloud mass sits on the left side of the frame and a wispy strand-like cloud sits on the right side, with a visible gap or boundary between them; however, at least one of the two lacks its defining shape, e.g., the left-side cloud has no rounded, cauliflower-like bulges, or the right-side cloud is not thin and strand-like.
level_4: The left side shows a cumulus cloud with rounded, cauliflower-like bulges and a clearly defined outer edge; the right side shows a cirrus cloud made of thin, hair-like strands; the two cloud regions stay clearly separated left/right with no strands crossing into the cumulus region or puffy tufts crossing into the cirrus region.
level_5: The cumulus cloud on the left keeps full, rounded, cauliflower-like volume with crisp lateral edges; the cirrus cloud on the right keeps continuous, unbroken, thread-like strands with occasional fine branching; the left/right division stays clean and in the same place across the full 10 seconds, with neither cloud drifting into the other's half of the frame or changing into the other's shape.

Scientific and Causal Correctness rubric:
level_1: The cumulus cloud on the left shows no upward growth or billowing at all over the 10 seconds (it looks frozen or only drifts sideways like the cirrus), or the cirrus cloud on the right shows turbulent churning or vertical bulging rather than a steady horizontal drift.
level_2: The cumulus cloud grows or changes shape in a way that looks turbulent or chaotic rather than steady upward billowing; or the cirrus strands bunch, clump, or curl instead of drifting together along one direction; the two clouds' behaviors are not clearly distinguishable from each other.
level_3: The cumulus cloud shows visible upward billowing consistent with rising, buoyant air, and the cirrus cloud shows the strands drifting steadily in one consistent direction consistent with being carried by upper-level wind; the two behaviors are distinguishable from each other, but the connection to their respective formation processes (convective versus wind-driven) is only weakly conveyed.
level_4: The cumulus cloud's upper surface visibly domes and swells outward over time, consistent with a rising thermal of moist air; the cirrus strands all move together at the same steady speed and in the same direction, consistent with being carried passively by high-altitude wind rather than growing on their own; the two clouds' motions read as clearly different mechanisms.
level_5: The cumulus cloud shows distinct turret-like bulges rising and swelling continuously over the full 10 seconds, consistent with sustained convective updraft; the cirrus strands drift smoothly and uniformly at a constant apparent speed with no bulging, thickening, or self-generated growth, consistent with passive advection by wind shear alone; the contrast between self-driven vertical growth (cumulus) and externally-driven horizontal drift (cirrus) is unambiguous throughout.

Spatiotemporal Consistency rubric:
level_1: A cloud abruptly jumps to a new position, vanishes and reappears, or breaks apart into disconnected floating fragments; the frame's scale suddenly jumps in or out; the whole scene appears to invert or flip between frames.
level_2: A cloud's position shifts noticeably between frames without any smooth motion connecting the two positions; the boundary between the cumulus and cirrus regions flickers in and out; the sun's apparent direction changes, or shadows appear and disappear, with nothing in the scene to explain it; the horizon tilts or the vanishing point shifts.
level_3: Both clouds stay on their assigned side of the frame throughout; there is no jumping, vanishing, or fragment-like breakup; however, the motion is uneven: the cumulus growth or cirrus drift speeds up and slows down abruptly at least twice, or the overall brightness noticeably pulses, or the horizon shows a slight, visible wobble while still remaining readable as a horizon.
level_4: The cumulus stays on the left and cirrus on the right throughout, with the boundary between them holding steady; any growth or drift is smooth and moves in one consistent direction at a steady pace; the sun's position and the direction of shadows stay the same across the full sequence; the horizon line stays straight and doesn't move; there is no visible tearing or warping where the clouds meet the sky.
level_5: The cumulus and cirrus regions keep the same relative position, size, and orientation across the whole video except for the cumulus's own upward growth and the cirrus's own lateral drift, both of which move at a constant, natural pace with no sudden speed changes; the lighting comes from a single consistent source with no stray glare or flare; the horizon stays level and visibly unmoving for the entire 10 seconds.