Bishop Bio 103 greenhouse effect

Energy Conversion and Greenhouse Effect

  • Energy loss through various mediums.

    • Example: Energy lost when a car passes through glass or atmosphere due to interaction with gas molecules.

  • Accumulation of gas molecules increases difficulty for radiation (heat) to escape.

Greenhouse Gases

  • Examples of greenhouse gases:

    • Carbon dioxide (CO₂)

    • Methane (CH₄)

    • Hydrofluorocarbons (HFCs)

    • Nitrous oxide (NOₓ)

    • Fluorinated compounds

  • Impact of greenhouse gases:

    • Increase in global temperatures and greenhouse effect.

Global Warming Potential (GWP)

  • Definition: A measure of how much heat a greenhouse gas traps in the atmosphere compared to CO₂ over a specific time period.

  • Significance:

    • Indicates the potential of a gas to contribute to global warming.

  • Baseline Comparison:

    • GWP is compared to CO₂ as the standard (GWP of CO₂ = 1).

  • Examples of GWP:

    • Methane has a GWP of 21 (it is 21 times more effective than CO₂ in trapping heat).

    • HFCs can have a GWP of up to 1000 times that of CO₂.

Concerns Regarding Global Warming Terminology

  • Importance of terminology in climate discussions:

    • "Global warming" reflects only temperature increases and doesn’t encompass all effects of climate change.

    • Examples of unintended consequences of global warming:

    • Melting glaciers leading to rising sea levels.

    • Changes in pH levels of oceans and extreme weather events.

  • Broader effects of climate change beyond just temperature rise.

Historical Temperature Records

  • Continuous monitoring of temperatures began in the 1870s with thermometers.

  • Limitations of historical data:

    • Only 150+ years of direct temperature measurements.

    • Other methods, like ice core analysis, can provide data spanning hundreds of thousands of years.

Ice Core Analysis

  • Methodology:

    • Ice cores extracted from glaciers in places like Antarctica.

    • Capture air bubbles from different periods (up to 600,000 years ago).

  • Purpose:

    • Provide indirect temperature records based on trapped gases within air bubbles.

    • Use of isotopic analysis to determine age of samples by comparing layers.

Glaciers vs. Ice Caps

  • Glacier: Terrestrial (land-based) ice which can form rivers or sheets.

  • Ice Cap: Floating ice formation, partially above water.

  • Locations of glaciers:

    • Significant glaciers in regions such as Greenland, Canada, and Montana (Glacier National Park).

    • Mount Kilimanjaro in Africa also has glaciers, but they are rapidly disappearing.

Impacts of Climate Change on Biodiversity

  • Current impact on species and biodiversity:

    • Extinction risk of many species due to changing climate.

    • Overall biodiversity is at risk, affecting ecosystems.

    • Critical to save biodiversity to maintain natural balance.

Climate Change Patterns and Trends

  • Rapid temperature increase is unprecedented compared to past natural fluctuations.

  • Potential for human-made factors (anthropogenic causes) driving climate change.

Feedback Loops and Albedo Effect

  • Positive feedback loops due to melting ice:

    • Loss of reflective snow and ice increases heat absorption, leading to further warming.

  • Albedo effect:

    • Surfaces covered in ice reflect sunlight, while darker surfaces increase heat absorption.

Discussion about Ocean Currents

  • Importance of ocean currents like the Gulf Stream:

    • Moderates climate in Western Europe.

    • Impact of melting glaciers on salinity and temperature of ocean currents.

  • Misrepresentation in media:

    • Movies like "The Day After Tomorrow" suggest rapid climate shifts that are scientifically implausible.

Climate and Precipitation Patterns

  • Climate change alters precipitation patterns:

    • Regions that are inherently wet become wetter, while dry regions become drier.

    • Water scarcity is becoming a profound issue:

    • Example: Great Lakes coalition to prevent water diversion due to climate concerns.

    • Increasing conflict in regions experiencing drought due to competition for limited water resources.

Conclusion

  • Reinforcement of the idea that while ecosystems may shift, the planet itself will endure.

  • Importance of biodiversity and human survival in the context of climate change.

  • Encouragement to study environmental science for deeper understanding of these issues.