Environmental Science Overview

Human's Role in the Environment

• Humans are part of the natural world and dependent on a healthy planet.
• Human activities impact the environment in various ways.
• Sustainability is crucial for future generations.
• Environmental science studies the natural world and human impact.

Environmental Science

• Environmental science is an interdisciplinary field using natural, social, and humanities sciences.
• Natural sciences examine the climate, organisms, energy, and matter flow within an environment.
• Social sciences address environmental policies suitable for different cultures and how societal acceptance of changes influences sustainability.
• Humanities consider how religion and tradition impact environmental choices and expressions of emotions toward nature.
• Environmental problems are multifaceted, involving multiple causes, consequences, and stakeholders with differing solutions.
• Solutions often involve trade-offs that must be considered.

Environmental Problems and Solutions

• Climate change, deforestation, and overconsumption are significant environmental issues.
• Climate change involves multiple causes (e.g., burning fossil fuels) and consequences (e.g., sea level rise).
• Stakeholders have differing interests regarding solutions, and solutions often involve tradeoffs (e.g., alternative energy sources vs. fossil fuels; reforestation vs. agriculture).
• Environmental problems require a triple bottom line approach: environmental, societal, and economic considerations need to be addressed for sustainable solutions.

Sustainable Development

• Sustainable development satisfies present needs without compromising future generations' ability to do the same.
• The United Nations advocates for sustainable development through the 2030 Agenda.
• The 2030 Agenda includes 17 Sustainable Development Goals (SDGs) focused on human concerns and environmental issues.

Sustainable Ecosystems

• Sustainable ecosystems rely on renewable energy (solar, wind etc.), recycle matter, and maintain appropriate population control dependent on local biodiversity and human contributions.
• Humans can mimic sustainable ecosystem characteristics to achieve sustainability.
• Ecosystem organization ranges from small scales (e.g., rotting logs) to large scales (e.g., continents).

Challenges to Sustainability

• Short-term thinking (social traps) contributes to environmental problems.
• Addressing social traps involves understanding ecosystem processes, considering long-term consequences, and enacting regulations on shared resources.
• Ecosystems are complex assemblages of living (biotic) and non-living (abiotic) components with intertwined processes (e.g., nutrient cycles, predation).

Principles of Ecosystem Function

• Matter and energy are conserved (neither created nor destroyed).
• Ecosystems are open to exchanges of matter and energy.
• Ecosystem processes are self-regulated through feedback mechanisms.
• Ecosystem change is essential and inevitable.

Energy and Matter

• The first law of thermodynamics states that energy cannot be created or destroyed, only transformed.
• The second law of thermodynamics states that energy transformations are not 100% efficient, and some energy is always lost as heat.
• Matter (e.g., chemicals) cannot be created or destroyed, and is recycled within ecosystems.
• Ecosystems gain and lose energy and matter, which is then transformed within the ecosystem.

Uncertainty in Environmental Science

• There is significant uncertainty about complex environmental issues like biodiversity loss.
• Uncertainty comes from ignorance (lack of knowledge) and complexity (understanding interactions between parts of the system).
• Scientific certainty increases with evidence but never reaches absolute proof. Science is a process, not a fixed set of facts.

Scientific Method

• Science uses the scientific method to empirically test hypotheses.
• Hypothesis: testable explanation.
• Scientific claims are based on empirical observations, which are verifiable by the senses or instruments.

Environmental Policy

• Policies address a desired outcome or goal and must consider a triple bottom line approach.
• Science provides information necessary to propose and inform needed policies, for example, the precautionary principle.
• Precautionary principle: action that prevents harm when data is uncertain or consequences are severe.
• Drafting and implementing policy can be challenging due to multiple complexities.