In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them

In X: some UV & most visible radiation from the Sun is transmitted through the atmosphere to the Earth's surface. In Y: IR radiation is emitted by the Earth's surface & transmitted out to space without being absorbed by the atmosphere. X & Y are called "windows" because radiation is transmitted through them