APES Notes 1.7 - Hydrologic (Water) Cycle
Summary
TLDRIn this educational video, Mr. Smeeds explores the hydrologic cycle, detailing how water transitions between solid, liquid, and gas states, and moves between various reservoirs such as the atmosphere, bodies of water, and underground aquifers. Key processes like evaporation, transpiration, and precipitation are explained, emphasizing the sun's role in driving the cycle. The importance of understanding these processes for human use of freshwater is highlighted, along with the environmental implications of runoff and infiltration.
Takeaways
- 🌊 The hydrologic cycle, also known as the water cycle, involves the movement of water in different states between various sources and reservoirs.
- 💧 Water's state of matter, whether solid, liquid, or gas, is crucial in understanding its movement within the cycle.
- 🌤️ Precipitation, such as rain, represents water transitioning from a gaseous state in the atmosphere to a liquid state on Earth's surface.
- 🌍 The hydrologic cycle is driven by solar energy, which causes water to evaporate from bodies of water and transpire from plants.
- 🌊 The largest reservoir of water on Earth is the ocean, while smaller but significant freshwater reservoirs include polar ice caps, glaciers, and groundwater.
- 🌿 Transpiration is the process by which plants draw water from the ground and release it into the atmosphere through stomata in their leaves.
- 🌡️ Evapotranspiration is the combined process of evaporation and transpiration, representing the total water vapor released into the atmosphere from an ecosystem.
- 💧 Runoff occurs when precipitation flows over the Earth's surface and eventually reaches bodies of water, contributing to surface water reservoirs.
- 🌱 Infiltration is the process where water from precipitation soaks into the ground, replenishing aquifers and groundwater supplies.
- 🌳 The permeability of the ground cover significantly affects the amount of water that can infiltrate and recharge groundwater reservoirs.
Q & A
What is the hydrologic cycle?
-The hydrologic cycle is the movement of water in different states between various sources and reservoirs, driven by energy from the sun.
How does precipitation relate to the hydrologic cycle?
-Precipitation is a part of the hydrologic cycle where water in the atmosphere condenses into clouds and falls back to Earth as liquid, moving from the atmospheric reservoir to the surface water or groundwater reservoirs.
What are the two key reservoirs water might move to after precipitation?
-After precipitation, water might move to surface water bodies or infiltrate into the ground to become groundwater.
What is the role of the sun in the hydrologic cycle?
-The sun provides the energy necessary to drive the hydrologic cycle, particularly in processes like evaporation, where it warms water bodies causing water to evaporate and enter the atmosphere as a gas.
What is the largest reservoir of water on Earth?
-The largest reservoir of water on Earth is the ocean.
Why are polar ice caps, glaciers, and groundwater important?
-Polar ice caps, glaciers, and groundwater are important because they are significant freshwater sources that humans can use for agriculture and drinking, unlike the saltwater from the ocean.
What is transpiration and how does it relate to the hydrologic cycle?
-Transpiration is the process where plants draw water from the ground via their roots and release it as water vapor through their leaves, contributing to the water cycle by moving water from the liquid state on Earth to the gaseous state in the atmosphere.
What is evapotranspiration and how does it contribute to the water cycle?
-Evapotranspiration is the sum of water lost to the atmosphere from both evaporation and transpiration. It represents the total amount of water that leaves an ecosystem in the form of water vapor, driven by the sun's energy.
What are the two possible outcomes for precipitation when it reaches the Earth's surface?
-When precipitation reaches the Earth's surface, it can either flow across the surface as runoff into a body of water or it can infiltrate into the ground and become part of the groundwater.
How does the permeability of the ground cover affect groundwater recharge?
-The permeability of the ground cover affects groundwater recharge by determining how easily water can infiltrate the soil and reach underground aquifers. More permeable surfaces, like those covered by grass and soil, allow for greater infiltration and recharge of groundwater.
Why is runoff important for human use, but also a potential problem?
-Runoff is important for human use because it replenishes surface bodies of water, which are crucial for drinking and agriculture. However, it can also be a problem because as it flows over the surface, it can pick up pollutants, which then get carried into water bodies, potentially causing environmental and health issues.
Outlines
💧 Understanding the Hydrologic Cycle
Mr. Smeeds introduces the hydrologic or water cycle, emphasizing its importance as a biogeochemical cycle. He outlines the objective to explain the steps and reservoir interactions within the cycle. The discussion focuses on the states of matter water travels in and the reservoirs it moves between, such as precipitation from the atmosphere to earth's surface as liquid. The video highlights the significance of the sun's energy in driving the cycle, with examples of water reservoirs including oceans, polar ice caps, glaciers, and groundwater. The importance of fresh water sources for human use is also stressed.
🌿 Exploring Evapotranspiration and Its Impact
The script delves into the processes of evaporation and evapotranspiration, explaining how water transitions from liquid to gas form in the atmosphere. Transpiration, the process by which plants absorb water and release it through stomata, is detailed. The concept of evapotranspiration, which encompasses both evaporation from surfaces and transpiration from plants, is introduced as a key component of the water cycle. The video also addresses the processes of runoff and infiltration, explaining how water either flows over surfaces or seeps into the ground, replenishing surface and groundwater reservoirs. The importance of permeability for groundwater recharge and the potential pollution issues associated with runoff are also discussed.
Mindmap
Keywords
💡Hydrologic Cycle
💡Reservoirs
💡Precipitation
💡Evaporation
💡Transpiration
💡Evapotranspiration
💡Infiltration
💡Runoff
💡Polar Ice Caps and Glaciers
💡Aquifers
💡Permeability
Highlights
Introduction to the hydrologic cycle as a biogeochemical cycle.
Objective to explain the steps and reservoir interactions in the water cycle.
The hydrologic cycle involves the movement of water in different states between sources and reservoirs.
Focus on the state of matter of water (solid, liquid, gas) and its movement between reservoirs.
Precipitation as an example of water moving from gas in the atmosphere to liquid on Earth's surface.
Reservoirs water might move to include surface water bodies or groundwater.
The hydrologic cycle is driven by energy from the sun.
The largest reservoir of water on Earth is the ocean.
Polar ice caps, glaciers, and groundwater are important freshwater sources.
Evaporation and evapotranspiration are key processes moving water from liquid to gas form.
Transpiration is the process by which plants draw water up from the ground and release it through leaves.
Stomata are the pores in plant leaves that facilitate transpiration.
Evapotranspiration is the sum of water lost through evaporation and transpiration.
Sun's energy drives both evaporation and transpiration.
Runoff and infiltration are processes that occur when precipitation reaches Earth's surface.
Runoff is the flow of water across the surface into bodies of water.
Infiltration is the process where water soaks into the ground and reaches aquifers.
Permeability of ground cover is crucial for groundwater recharge.
Runoff contributes to surface water bodies but can also carry pollutants.
Practice FRQ to explain relationships between concepts in a visual model of the water cycle.
Transcripts
hey everybody it's mr smeeds and today
we'll be covering topic 1.7
which is the hydrologic or water cycle
just like in all of the other
biogeochemical cycles we've covered
we'll be looking at how water moves
between sources and sinks
our objective for the water cycle is to
be able to explain the steps and
reservoir interactions
in the cycle and at the end of the video
we'll practice the scientific skill
of explaining differences between
environmental concepts
using a visual model so the hydrologic
cycle is the movement of water
in different states between different
sources and reservoirs
and so in this cycle we like to focus on
first of all what state of
matter that water is traveling in
whether that's solid liquid or gas
but then also where is the water moving
so
what reservoir is it leaving and what
reservoir is it entering
so for example we could look at
precipitation which we
probably know already as rain and that
is going to be
water moving from a gas in the
atmosphere as it condenses together into
clouds
and then eventually falls back down to
earth as a liquid so the reservoir it's
leaving as the atmosphere
and the reservoir it's entering is a
little bit trickier it's going to be
hitting earth's surface
and it could run off into a body of
water then it would be entering what
we'd call a surface water or a body of
water
or it could infiltrate into the ground
and it could become
groundwater so those are the two
reservoirs water might be moving to
really important to know that the
hydrologic cycle is driven by energy
from the sun
this is kind of a tricky concept but
think about a body of water
as the sun hits that body of water
that's going to cause the water at the
surface to warm
and eventually turn into a gas and
evaporate
the largest reservoir of water on earth
is the ocean that's important to know
but two smaller reservoirs are polar ice
caps glaciers and ice caps found on
mountains
as well as ground water these are very
important because they're fresh water
sources
so humans can't use salt water from the
ocean for things like agriculture or
drinking
but we can use these fresh water sources
so even though they're a lot
smaller it's really important that we
remember these are our
key freshwater sources now we'll talk
about evaporation
and evapotranspiration so these are the
two key
sources or processes that move water
from a liquid form
on earth into a gas form in the
atmosphere
sometimes we call this the vaporization
of water because it's
liquid water transforming into a vapor
or gas that enters the atmosphere so
transpiration
is this process where plants are going
to draw water
up from the ground via their roots and
up into their stem and their leaves and
other
places in the plant that need water so
they do this with a really neat trick
and they are going to use these little
pores in their leaves called stomata
so the stomata open up so if we look at
the diagram here we can see these
pores basically in the leaf are going to
open and water vapor
is going to evaporate due to the sun's
energy what that does is creates a
low pressure system where the leaf
has a lower water pressure than the
roots and that's going to draw water
up from the roots to replace that water
in the leaf that evaporated
so in the diagram here we can see the
water that's in the ground will be drawn
up the roots up the stem and to the
leaves because we have a low water
pressure in the leaves
as they open their stomata and allow the
sun's energy to cause some
transpiration so again as a summary
transpiration
is the process of a plant drawing water
up from the ground via its roots
by allowing some of the water in its
leaves to evaporate
now we have a concept called
evapotranspiration
and evapotranspiration is just a way to
add up the total amount of water
leaving an ecosystem by both
transpiration
and evaporation so if we look at the
diagram the water that evaporates from
the soil or from bodies of water
combined with the water that leaves
plant stomata
via transpiration would be considered
evapotranspiration
really important to remember that both
processes are driven by the sun
so when the sun's rays strike the soil
some of the moisture in that soil will
be heated up and it will evaporate as a
gas in the atmosphere
and same thing with the leaf when the
leaf has its leaves warmed by the sun
and it opens its stomata some of the
liquid water in that leaf
will evaporate as a gas and again that's
how the leaf is going to actually draw
more water up from the roots
and finally we'll talk about runoff and
infiltration
so when precipitation falls to earth's
surface it can do one of two things it
can either flow across the surface until
it reaches
a body of water as runoff or it can
slowly trickle into underground water
stores called aquifers
and we call that process infiltration so
we can look at the
diagram here and we can see that if the
water hits earth's surface
and just flows into a body of water we'd
call that surface runoff
but if it hits the ground and it's able
to soak into the ground and eventually
reach an
aquifer or an underground water storage
we would call that infiltration
now these two processes are very
important because they contribute water
to very important freshwater reservoirs
so runoff will recharge
surface bodies of water which are
important drinking sources for humans
and important sources for agriculture
but they'll also recharge groundwater
which can be especially important water
sources in dry areas where humans have
to use a well to drop water from the
ground
so remember that precipitation is going
to recharge groundwater
only if that water falling can
infiltrate
the soil so if we look at this diagram
here to help us understand that
if we have a surface that is covered by
grass and soil
that's going to allow a lot of the water
to infiltrate or to soak into the ground
and recharge those aquifers underground
but on the right hand diagram we have a
surface that's not very permeable
meaning it doesn't allow water to easily
trickle through
and so far more of that water is going
to leave the area as runoff
so permeability or the ability of
a ground cover to allow water to soak
through and
into the aquifers beneath it is really
important for groundwater recharge
runoff on the other hand is going to
eventually recharge surface waters it
will return water that fell as
precipitation
to a lake or a river or a pond and
that's an important source for humans to
use
but one drawback of this is that the
runoff
gathers pollutants on its way to the
surface body of water
and so we'll be talking about these
issues in a lot more depth when we get
to our water unit later in the year
our practice frq for topic 1.7 today
will cover the skill of explaining
relationships between concepts in a
visual model
so what i want you to do is take a look
at this diagram of the water cycle
and there are four different letters you
have a b c and d
i want you to choose one of those
letters and identify the process that's
being shown
then describe how water is moving from
one reservoir
to another reservoir by that process
all right everybody thanks for tuning in
today don't forget to like this video if
it was helpful
subscribe for future apes video updates
and check out other notes over here to
the side
and as always think like a mountain
write like a scholar
5.0 / 5 (0 votes)