← Back to catalogue
Research draft

albedo

vr.tr.albedo · XCT.REL

Let an agent state albedo with its type, wavelength range and source, and use it correctly in climate and astronomy.

Thing Registry Cross-cutting context

Research draft, second pass

A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.

written by Claude from model knowledge without web access - no source was read, every claim is a lead to verify

Researched by: Claude

Purpose and description

Let an agent state albedo with its type, wavelength range and source, and use it correctly in climate and astronomy.

The fraction of incident light or radiation that a surface or body reflects, from 0 (perfect absorber) to 1 (perfect reflector), with variants such as Bond albedo and geometric albedo.

What it is for: Describing reflectivity of surfaces, planets and snow, and its role in climate.

It can be measure it by satellites and instruments; compare surfaces; use it in climate and energy models; estimate sizes of asteroids from brightness.

Distinguishing features

Ratio of reflected to incident radiation

Depends on wavelength and angle

Different definitions in astronomy

Key feedback in climate

What it looks like

Not visible as such; bright surfaces like snow have high albedo, dark ones like forests low.

Physical character

fresh snow: 0.8-0.9 dimensionless

ocean: about 0.06 dimensionless

Earth average: about 0.3 dimensionless - Bond albedo

How it is recognised

Values between 0 and 1

Types such as Bond or geometric albedo

Satellite albedo maps

Related models

is a kind of - dimensionless quantity

ratio

affects - feedback

climate

is used for - astronomy

asteroid size estimates

is measured by - remote sensing

measurement

In practice

Families and kinds

Bond albedo

geometric albedo

surface albedo

spectral albedo

Failure modes and hazards

Mixing albedo types

Ignoring wavelength dependence

Also called

Bond albedogeometric albedo

Where this came from

wikidata · CC0 1.0

Drafted structure

Bundle to layer to finding to question, as the second pass will find it: 4 bundles · 8 layers · 8 findings · 16 questions.

Definition Which albedo.

Type must be stated.

Type

Bond, geometric, surface.

Type

Albedo type.

  1. Which albedo type is meant? definition
  2. Over which wavelengths? definition

Value

Number.

Value

The value.

  1. What is the albedo value? measurement
  2. From which source? provenance
Measurement How measured.

Methods affect values.

Method

Satellite or ground.

Method

Measurement method.

  1. How was it measured? provenance
  2. Under which illumination? definition

Uncertainty

Error.

Uncertainty

Uncertainty.

  1. What is the uncertainty? measurement
  2. How does it vary seasonally? measurement
Climate Role in climate.

Albedo changes affect warming.

Feedback

Ice-albedo feedback.

Feedback

Climate feedback.

  1. How does albedo change affect climate here? definition
  2. What does IPCC assess? provenance

Interventions

Cool roofs.

Interventions

Albedo interventions.

  1. Do cool roofs or other interventions change albedo usefully? measurement
  2. What are the trade-offs? boundary
Astronomy Planets and asteroids.

Albedo helps estimate sizes.

Size estimates

From brightness.

Size

Size estimates.

  1. How does albedo affect size estimates of small bodies? definition
  2. How uncertain are they? measurement

Planets

Planetary albedo.

Planets

Planetary albedo.

  1. What is the albedo of this planet or moon? measurement
  2. Which mission measured it? provenance

What the second pass must settle

  • Should albedo types be separate entries?
  • How should wavelength bands be recorded?
  • How should satellite products be linked?