Weather and Climate Overview

Weather vs. Climate

• Weather describes the short-term atmospheric conditions.
• Climate describes long-term patterns of temperature and precipitation.

The Greenhouse Effect

• The greenhouse effect is the trapping of heat by gases in the atmosphere.
• Sunlight passes through the atmosphere, some is reflected, and some is absorbed by the Earth.
• Greenhouse gases (e.g., carbon dioxide, methane, nitrous oxide, water vapor) trap some of the heat, warming the Earth's surface.

Greenhouse Gases

• Carbon dioxide
• Methane
• Nitrous oxide
• Water vapor

Earth's Seasons

• Earth's tilt and revolution around the sun cause the seasons.
• Uneven distribution of solar heat due to varied angles of sunlight.

Latitudinal Regions

• Tropical: 0 degrees
• Temperate: 30-60 degrees
• Polar: 60-90 degrees

Atmospheric Pressure

• Hot air rises, creating low pressure.
• Less dense air exerts less pressure.
• Cold air sinks, creating high pressure.
• Dense air exerts more pressure.
• Low pressure areas are near the equator; high pressure areas are near the poles.
• Low-pressure areas are associated with more precipitation, affecting climates and biomes, like wetlands and rainforests.

Mountains and Precipitation

• Mountains force rising air, leading to cooling and condensation, causing rain on the upwind side.
• The downwind side (rain shadow) receives much less precipitation.

Wind Movement

• Surface winds move from high-pressure to low-pressure areas.
• The Coriolis Effect deflects winds to the right in the Northern Hemisphere and left in the Southern Hemisphere.

Ocean Currents

• Factors impacting ocean currents include solar heating, winds, salinity, density, and Earth's rotation.
• Upwelling brings nutrients to the surface of the ocean.

El Niño and La Niña

• El Niño: High pressure moves to the Americas, low pressure to Asia, slowing trade winds and reducing upwelling, causing precipitation changes in each region. -La Niña: High and low pressure areas are more extreme, causing stronger trade winds, and more upwelling, causing weather changes in both regions.

Photosynthesis

• Photosynthesis is the process in which organisms convert sunlight, water, and carbon dioxide into energy-rich carbohydrates and oxygen.
• Producers, like plants, perform photosynthesis.

Chemosynthesis

• Chemosynthesis produces carbohydrates using chemical energy, such as hydrogen sulfide, instead of sunlight.
• Bacteria and archaea perform chemosynthesis in hydrothermal vents and cold seeps, utilizing hydrogen sulfide and dissolved carbon dioxide as sources.

Mutualistic Relationships

• Tubeworms and chemosynthetic bacteria have a mutualistic relationship, where the bacteria feed the worms.

Trophic Levels

• Trophic levels are positions in a food chain.
• Producers are at the bottom of the food chain.
• Consumers (herbivores, carnivores, omnivores, detritivores, decomposers, scavengers) make up the levels above producers.

Food Webs vs. Food Chains

• Food webs are networks of interconnected food chains.
• Food chains show a single path of energy flow.

Invasive Species

• Invasive species can disrupt food webs by competing for resources, affecting other organisms within the food web

Energy Transfer in Trophic Levels

• Energy is transferred from one trophic level to the next, but only a portion is available to the next level (10% rule:).

The Water Cycle

• Evaporation: Liquid to gas
• Transpiration: Water vapor from plants
• Condensation: Water vapor forms clouds
• Precipitation: Water falls to Earth
• Runoff: Water flows over land
• Seepage (percolation): Water seeps into the ground
• Aquifer: Underground water reservoir
• The largest reservoir: Ocean
• Abiotic factor: The sun's energy

The Carbon Cycle

• Photosynthesis: Producers absorb CO2
• Cellular respiration: Organisms release CO2
• Deforestation: Removes carbon sinks
• Burning fossil fuels: Adds CO2 to the atmosphere
• Largest reservoir: Sedimentary rock

The Nitrogen Cycle

• Nitrogen fixation: Bacteria convert nitrogen gas to ammonia and ammonium.
• Nitrification: Bacteria convert ammonia to nitrites and nitrates.
• Assimilation: Producers absorb nitrates; animals obtain nitrogen by consuming organisms.
• Ammonification: Decomposition of waste and dead organisms releases ammonia.
• Denitrification: Bacteria convert nitrates back to nitrogen gas.
• Largest reservoir: Atmosphere

The Phosphorus Cycle

• Weathering/erosion: Release of phosphates
• Assimilation: Producers absorb phosphates; animals obtain phosphorus by consuming organisms.
• Decomposition: Creates inorganic phosphates
• Sedimentation: Accumulation of phosphate-containing sediments.
• Largest reservoir: Sedimentary rock

Fertilizers and Water Pollution

• Runoff from fertilizers carries nitrogen and phosphorus into bodies of water.
• This excess nitrogen and phosphorus cause algal blooms.
• Algal blooms lead to oxygen depletion and fish kills and also produces toxins.

Wetlands

• Wetlands perform water purification, provide habitat, and control flooding.
• Farmers should consider wetland locations, size, and water depth for certain species.