Introduction to
Environmental
Science and
Engineering
Environmental Science and Engineering
Environmental Science studies how natural systems
function and how humans impact them.
Environmental Engineering applies scientific principles to
develop solutions for environmental issues.
This combines various disciplines: such as biology,
chemistry, physics, and engineering to solve real-world
environmental problems.
Environmental
Science
Examines Earth's natural
processes, including the
atmosphere, hydrosphere,
biosphere, and lithosphere.
Studies the impact of human
activities such as
deforestation, pollution, and
climate change.
Helps develop strategies for
conservation, sustainability, and
resource management.
Environmental Engineering
Design solutions for pollution control, water treatment, and
waste management.
Develop renewable energy technologies like solar and wind
power.
Focuses on sustainable infrastructure, such as green
buildings and smart cities.
Addresses ongoing global challenges like climate change, pollution, and
resource depletion
Why is this
field Ensures there is clean air, water, and sustainable resources for future
generations
important?
Supports technological innovation for a greener and more sustainable world
Understanding Earth’s Systems
Earth’s systems
Earth’s environment is made up of four major systems:
Atmosphere, Hydrosphere, Biosphere, and Lithosphere.
These systems interact with each other, influencing
climate, ecosystems, and human activities.
Understanding these interactions helps us develop
solutions for environmental challenges.
Earth’s systems: Atmosphere
The atmosphere is a thin layer of gases surrounding Earth,
essential for life.
It protects us from harmful solar radiation and maintains
the planet’s temperature.
Human activities, like burning fossil fuels, have increased
greenhouse gases, contributing to climate change.
Oxygen
and
Carbon
Cycle
Nitrogen
Cycle
Earth’s systems: Hydrosphere
The hydrosphere includes all of Earth’s water bodies:
oceans, rivers, lakes, groundwater, and glaciers.
The water cycle moves water through evaporation,
condensation, and precipitation.
Pollution from industries, agriculture, and plastic waste
threatens clean water sources.
Earth’s systems: Lithosphere
The lithosphere is Earth’s solid outermost layer, including
rocks, soil, and landforms.
It provides natural resources, such as minerals, fossil fuels,
and fertile soil for agriculture.
Overuse of land through mining, deforestation, and
urbanization leads to soil degradation and erosion.
Earth’s systems: Biosphere
The biosphere consists of all living organisms on Earth,
from microbes to plants and animals.
Ecosystems provide essential services, such as oxygen
production, food, and climate regulation.
Human activities, like deforestation and habitat
destruction, are causing biodiversity loss.
Human Impact
on Earth’s
Systems
Industrialization and
urbanization have
increased pollution,
deforestation, and climate
change.
Activities such as burning
fossil fuels and waste
dumping disrupt natural
processes.
Sustainability and Carrying Capacity
Sustainability means meeting present needs without
compromising future generations.
Earth’s carrying capacity is the maximum population it can
support without depletion of resources.
Sustainable development balances economic growth,
environmental protection, and social well-being.
Major Environmental Issues
Overview
Global temperatures have risen by
1.1°C since pre-industrial times due to
greenhouse gas emissions (IPCC,
2021).
The world generates 2.01 billion metric
tons of solid waste annually, with only
19% recycled (World Bank, 2022).
Over 1 million species face extinction
due to human activities (UN Biodiversity
Report, 2019).