NASA | Earth's Water Cycle

NASA Goddard

3 Aug 201205:53

Summary

TLDRThis video script delves into the vital role of water on Earth, highlighting its scarcity and distribution. It explains the water cycle's dynamics, from evaporation influenced by temperature and wind to precipitation's impact on ecosystems. The script underscores the importance of water storage in ice caps, lakes, and aquifers, and the challenges posed by climate variability and human demand. NASA's satellite observations are crucial for understanding water's availability amidst climate change and population growth.

Takeaways

🌎 Earth's vast oceans give the impression of abundant water, but only a small portion is accessible for human use.
❄️ Nearly two-thirds of Earth's fresh water is stored in polar ice caps, snow packs, and glaciers, making it inaccessible for long periods.
🔁 The water cycle is a dynamic process involving the continuous movement and state transitions of water on, above, and below the Earth's surface.
🌡️ Factors like sea surface temperature, surface winds, and air temperature influence the rate of evaporation, particularly in the tropics where warm temperatures support high evaporation rates.
💨 The atmosphere, despite not holding much water, can quickly transport it from one place to another, forming 'atmospheric rivers' under certain conditions.
🌧️ Clouds form as water vapor cools and condenses, and they play a crucial role in the Earth's climate by acting as insulators and affecting temperature regulation.
⛈️ Storms can grow into large systems that transfer heat vertically and help distribute it between the equator and poles, shaping global wind patterns.
🌧️ Precipitation varies greatly across the world, being concentrated in some areas and scarce in others, with significant seasonal and annual variations.
🏞️ Precipitation that falls on land is stored in various forms such as snow packs, lakes, reservoirs, soils, and underground aquifers.
🌿 Water availability influences the type and abundance of vegetation, which is the primary source of food for animals and people.
🌊 NASA satellites equipped with sensors observe and measure water on land, in the ocean, and in the atmosphere, helping us understand its availability and distribution in the context of climate change and population growth.

Q & A

What is the fundamental ingredient for life on Earth?
-Water is the fundamental ingredient for life on Earth.
Why might Earth appear to have an abundance of water when viewed from space?
-Earth appears to have an abundance of water due to its vast and deep oceans, but only a small portion of this water is accessible for human use.
Where is the majority of Earth's fresh water stored, and why is it inaccessible for long periods?
-Nearly two-thirds of Earth's fresh water is stored in polar ice caps, snow packs, and glaciers, making it inaccessible for long periods of time due to its location and state.
What is the water cycle and why is it important?
-The water cycle is the continuous movement of water on, above, and below the Earth's surface, including transitions between different states. It is important because it describes the dynamic process that makes water available for life on Earth.
How do sea surface temperature, surface winds, and air temperature influence the water cycle?
-These factors influence the rate of evaporation at the ocean surface, with warmer temperatures and wind supporting higher rates of evaporation, which is a key part of the water cycle.
What is an 'atmospheric river' and how does it transport water?
-An 'atmospheric river' is a low-lying region of the atmosphere with high moisture and strong winds that can transport water horizontally over large distances.
How do clouds form and what role do they play in the atmosphere?
-Clouds form as water vapor cools and condenses into droplets and ice crystals. They act as insulators in the atmosphere, helping to shield the Earth from the Sun and trap heat from below.
What happens when cloud particles grow large enough?
-When cloud particles grow large enough, they may fall out as rain or snow, contributing to precipitation.
How do storms contribute to the distribution of heat in the atmosphere?
-As storms grow, they transfer heat vertically into the upper atmosphere and their migration helps distribute heat between the equator and poles, shaping global wind patterns.
How does precipitation vary around the world and what factors influence it?
-Precipitation is concentrated in some parts of the world and scarce in others, varying substantially from season to season and year to year. Factors influencing precipitation include atmospheric moisture, surface temperatures, and wind patterns.
What happens to water that falls on land as precipitation?
-Water that falls on land as precipitation is stored within snow packs, lakes, reservoirs, soils, and underground aquifers. Some of it is absorbed by plant roots or drains into the water table, eventually evaporating back to the atmosphere or returning to the ocean via streams and rivers.
How do NASA satellites contribute to our understanding of Earth's water?
-NASA satellites observe and measure water on land, in the ocean, and in the atmosphere, providing crucial data for understanding the availability and distribution of Earth's water, which is vital to life and affected by climate change and population growth.

Outlines

00:00

🌏 Earth's Water: Availability and the Water Cycle

This paragraph emphasizes the critical role of water for life on Earth and the illusion of its abundance when viewed from space. It clarifies that only a small fraction of Earth's water is accessible, with a significant portion locked in polar ice caps, snow packs, and glaciers. The water cycle is described as a dynamic process involving continuous movement and state transitions, influenced by factors such as sea surface temperature, surface winds, and air temperature. The atmosphere's role in transporting water quickly is highlighted, along with the formation of 'atmospheric rivers.' The paragraph also explains the insulating function of clouds and water vapor, the process of precipitation, and the impact of storms on global wind patterns and heat distribution. It concludes with the variability of water availability, its effect on vegetation and food sources, and the economic and human costs of water-related hazards such as floods.

05:04

🛰️ NASA's Observations: Understanding Earth's Water

The second paragraph focuses on the technological aspect of understanding Earth's water resources through NASA's satellite sensors. These sensors observe and measure water in various states across land, ocean, and the atmosphere. The importance of these measurements is underscored for comprehending the availability and distribution of water, which is essential for life and is susceptible to climate change and population growth. The paragraph concludes with a beep sound, possibly indicating a transition or a

Mindmap

Keywords

💡Water

Water is the fundamental ingredient for life on Earth, as stated in the script. It is essential for all known forms of life. The video discusses the limited accessibility of Earth's water resources, emphasizing the scarcity of fresh water and its importance in sustaining ecosystems and human societies. The script mentions that only a small portion of Earth's water is accessible for our needs, highlighting the importance of water conservation and management.

💡Polar Ice Caps

Polar ice caps are large, thick layers of ice that cover the Earth's polar regions. They store a significant amount of the Earth's fresh water, as mentioned in the script. Nearly two-thirds of the fresh water is stored in these ice caps, snow packs, and glaciers, making it inaccessible for long periods. The script implies the role of polar ice caps in the global water cycle and their vulnerability to climate change, which can lead to rising sea levels and altered weather patterns.

💡Water Cycle

The water cycle is the continuous movement of water on, above, and below the Earth's surface, including its transitions between different states such as liquid, solid, and gas. The script describes the water cycle as dynamic, illustrating how it involves processes like evaporation, condensation, and precipitation. This cycle is crucial for distributing water across the planet and maintaining the balance of ecosystems.

💡Evaporation

Evaporation is the process by which water changes from a liquid to a gas or vapor. The script notes that sea surface temperature, surface winds, and air temperature influence the rate of evaporation, particularly in the tropics where warm ocean surface temperatures support high rates of evaporation. Evaporation is a key component of the water cycle, enabling water to move from the Earth's surface into the atmosphere.

💡Atmosphere

The atmosphere is the layer of gases surrounding the Earth, which plays a critical role in the water cycle by transporting water through processes like evaporation and precipitation. The script mentions that while the atmosphere does not store a large quantity of water compared to other bodies, it can quickly move water from one place to another, forming 'atmospheric rivers' and influencing weather patterns.

💡Clouds

Clouds are visible masses of water droplets or ice crystals suspended in the atmosphere. They form as water vapor cools and condenses, as described in the script. Clouds play a dual role in the atmosphere; they act as insulators by trapping heat and also contribute to the water cycle by releasing water as precipitation when the cloud particles grow large enough.

💡Precipitation

Precipitation is any form of water that falls from the atmosphere and reaches the Earth's surface, including rain, snow, sleet, and hail. The script discusses how precipitation is concentrated in some parts of the world and scarce in others, varying from season to season and year to year. Precipitation is a critical part of the water cycle, replenishing water sources on land and contributing to the availability of fresh water.

💡Snow Pack

A snow pack refers to a layer of accumulated snow that remains on the ground for an extended period. The script mentions that snowfall is stored as snow pack or ice, which is an important form of water storage, especially in colder climates. Snow packs play a role in regulating water availability throughout the year as they gradually melt and contribute to water sources.

💡Aquifers

Aquifers are underground layers of water-bearing permeable rock or unconsolidated materials from which groundwater can be extracted. The script refers to aquifers as one of the storage places for water that falls on the land surface as precipitation. Aquifers are a vital source of fresh water for drinking, agriculture, and industry.

💡Climate Change

Climate change refers to long-term changes in the Earth's climate, particularly a rise in global temperatures. The script highlights the vulnerability of Earth's water resources to the impacts of climate change, which can affect the availability and distribution of water, leading to more extreme weather events such as floods and droughts.

💡NASA Satellites

NASA satellites are used for various scientific and exploration purposes, including the observation and measurement of Earth's water resources. The script mentions that sensors on these satellites help in understanding the availability and distribution of Earth's water, which is vital for life and is affected by climate change and population growth.

Highlights

Water is the fundamental ingredient for life on Earth, with its vast oceans making it appear abundant, but only a small portion is accessible for use.

Nearly two-thirds of Earth's fresh water is stored in polar ice caps, snow packs, and glaciers, making it inaccessible for long periods.

The water cycle is a dynamic process involving continuous movement and state transitions of water on, above, and below Earth's surface.

Sea surface temperature, surface winds, and air temperature influence the rate of evaporation, particularly in the tropics where warm temperatures support high evaporation rates.

The atmosphere, despite not storing large quantities of water, can quickly transport water from one place to another.

Atmospheric rivers can form in low-lying regions with high moisture and strong winds, facilitating horizontal water transport.

Clouds are formed by the cooling and condensation of water vapor into droplets and ice crystals, acting as atmospheric insulators.

Clouds shield the Earth from the Sun and trap heat, influencing weather patterns and climate.

Precipitation, including rain or snow, occurs when cloud particles grow large enough to fall out, contributing to storm development.

Storms can grow into large systems, transferring heat vertically and influencing global wind patterns.

The growth and intensity of storms depend on atmospheric moisture, surface temperatures, and wind patterns.

Precipitation is unevenly distributed across the world, varying significantly from season to season and year to year.

Water that falls on land as precipitation is stored in various forms, such as snow packs, lakes, reservoirs, soils, and underground aquifers.

Water availability varies by location and over time, affecting vegetation types and food sources for animals and humans.

Extreme variability in the water cycle, including unusually dry or wet conditions, impacts humans worldwide, including through hazards like floods.

Most water that falls on land remains stored for weeks or more, with some absorbed by plants or draining into the water table.

NASA satellites observe and measure water on land, in the ocean, and in the atmosphere, providing crucial data for understanding Earth's water availability and distribution.

Understanding Earth's water is vital for life and is increasingly important due to climate change and a growing global population.