Unit 2: Climate Change

Vocabulary flashcards covering key terms and concepts from the video notes on climate change, hurricanes, and global climate policy.

Hurricanes (Tropical Cyclones)

Rapidly rotating storm systems with a low-pressure center (eye), strong winds, and heavy rain; form over warm tropical oceans; energy from evaporation and condensation; typically 100–2,000 km in diameter.

Eye of the hurricane

The calm, low-pressure center of a hurricane where descending air creates relatively clear conditions.

Low-pressure center

The central part of a hurricane around which air rotates; causes air to rise and storms to develop.

Nomenclature impact

Hurricanes are the name given to tropical cyclones in the Atlantic and NE Pacific; naming helps with communication and tracking.

Warm water requirement for hurricanes

Form over warm seas with water temperatures around 80°F (26.7°C) or higher and at least 160 feet deep.

Energy source for hurricanes

Evaporation of ocean water; this moisture condenses into clouds and falls as rain, fueling the storm.

Hurricane season (US)

June 1 to November 30; peak activity typically in September when ocean temperatures are warmest.

Storm surge

A rise in sea level caused by wind and pressure effects in a tropical cyclone; a leading cause of storm-related fatalities.

Components of storm surge

Wind-driven surge and pressure-driven surge; water piles up as the storm approaches land.

Hurricane formation process (air dynamics)

Warm, moist air rises from the ocean; a low-pressure space forms; surrounding air moves in, warms, and rises, creating a rotating system.

Eye formation and rotation

As rotational speed increases, a distinct eye forms at the center where air sinks.

Sustained wind speed threshold for hurricanes

Sustained winds must exceed 74 mph to be classified as a hurricane.

Hurricanes and climate change

Warmer oceans from climate change can promote formation and intensification, leading to higher wind speeds and more intense storms.

Katia, Irma, Jose (2017)

Examples of intense Atlantic hurricanes in 2017 used to illustrate hurricane activity.

Hurricane Harvey (2017)

Major rainfall event in Houston, Texas, with over 2 feet of rain and about $125 billion in damage.

Sea level rise (global)

Rising sea levels due to polar ice melt and thermal expansion; about 7 inches in the last century; could rise several feet by 2100.

Storm surge and fatalities

Higher sea levels and strong surge increase flooding and fatalities; storm surge accounts for a large share of storm deaths.

Consequences of polar ice melt

Melting ice raises sea level; affects salinity and ocean currents; reduces sea ice habitat for polar ecosystems.

Positive feedback (ice melt)

Loss of ice reduces albedo, causing more solar absorption and further warming and melting.

Sea ice loss and ecosystems

Melting sea ice disrupts polar ecosystems and alters heat exchange and ocean circulation.

Glaciers and freshwater

Glaciers store roughly three-quarters of Earth's freshwater; melting affects water resources and sea level.

Heat waves

Extreme heat events that kill more people annually than many other hazards; notable cases include Europe (2003) and the Pacific Northwest (2021).

Heat waves and droughts linked to fires

Hot, dry conditions worsen wildfires, as seen in events like Maui (2023).

Extreme rainfall events

Intense precipitation events (e.g., 2021 Belgium/Germany floods; 2021 Tennessee floods; 2023 Libya floods) linked to a warming climate.

Climate refugees

People forced to relocate due to climate impacts such as sea-level rise, drought, or extreme weather.

Expansion of disease vectors

Warmer climates can expand ranges of vectors like mosquitoes, increasing diseases such as malaria.

Paris Agreement (2015, COP21)

196 nations agreed to limit warming well below 2°C, with efforts to pursue 1.5°C; enhance transparency and climate finance.

Five key elements of the Paris Agreement

Strengthen climate actions; adapt to impacts; aim for net-zero long-term; enhance transparency; provide climate finance.

Climate finance goal (Paris)

Developed countries pledge to provide about $100 billion per year in climate finance until 2025.

COP28 (2024)

Goal to accelerate action toward Paris Agreement goals to keep warming below 2°C.

IPCC AR6 Synthesis Report

The 2023 synthesis summarizing climate science, including SSPs and climate projections.

Shared Socioeconomic Pathways (SSPs)

Scenarios describing future emissions and societal development: SSP1-2.6, SSP2-4.5, SSP3-7.0, SSP5-8.5.

Global warming projections (2081–2100)

Projected temperature changes under different SSP scenarios, increasing with higher emissions.

Global mean sea level rise projections (2100)

Predicted sea level rise from melting ice and thermal expansion, varying by emissions scenario.

Carbon cycle

Movement of carbon among atmosphere, surface ocean, deep ocean, vegetation, soils, and fossils; includes fossil fuel emissions and natural sinks.

Greenhouse gases (GHGs)

Gases like CO2, CH4, N2O, plus HFCs/PFCs/SF6; trap heat and drive the greenhouse effect.

The greenhouse effect

Solar radiation heats Earth's surface; infrared radiation is absorbed and re‑emitted by GHGs, warming the lower atmosphere and surface.

NASA climate vital signs (examples)

CO2 around 422 ppm (2023); global temperature up ~1.1°C since preindustrial; Arctic sea ice decline; ocean warming; ice sheets losing mass; methane rising.

State of the Climate 2022 finding

All three dominant greenhouse gases reached new record highs in 2022 (CO2, CH4, N2O).

El Niño and La Niña

Natural climate fluctuations in the Pacific that cause short-term departures from typical weather patterns.

Weather vs. climate

Weather: short-term atmospheric conditions; climate: long-term average of weather in a region.

Drought Monitor categories

Scale from DO (Abnormally Dry) to D4 (Exceptional Drought) indicating drought intensity and impacts.

Ocean energy storage in climate system

The oceans have absorbed the majority (about 90%) of excess energy trapped by greenhouse gases.

Net-zero emissions

Balancing emitted greenhouse gases with equivalent removals or offsets.

Renewable carbon tax

A policy instrument taxing carbon emissions to promote cleaner, renewable energy sources.

The carbon cycle diagram elements

Atmosphere, surface ocean, deep ocean, vegetation, marine life, rivers, sediments, and fossil fuels involved in carbon fluxes.

Cohesive climate policy indicators

Regular emission reporting, transparency, and accountability measures central to international climate agreements.