Weather and Climate

It's easy to confuse weather and climate, but they are DIFFERENT:\n\n- **WEATHER** — what's happening right now or this week\n- **CLIMATE** — weather patterns over MANY YEARS (30+)\n\nExample: "It's raining TODAY" is weather. "Seattle is RAINY in winters" is climate. Today you'll learn how scientists measure both and why climate change matters.

Weather is defined by 5 things:\n\n1. **Temperature** — how hot or cold\n2. **Humidity** — how much moisture in the air\n3. **Precipitation** — rain, snow, sleet, hail\n4. **Wind** — speed and direction\n5. **Cloud cover** — amount and type\n\nWeather scientists (METEOROLOGISTS) track all 5 daily.

Earth has major climate zones:\n\n- **TROPICAL** — hot year-round (Amazon, Caribbean)\n- **ARID (desert)** — dry all year (Sahara, Arizona)\n- **TEMPERATE** — mild with seasons (most of US and Europe)\n- **POLAR** — freezing year-round (Arctic, Antarctica)\n- **CONTINENTAL** — hot summers, cold winters (Midwest US, Russia)\n\nYour climate zone affects HOW you live — what you wear, eat, build, and grow.

Climate is shaped by:\n\n- **Latitude** — closer to equator = hotter\n- **Altitude** — higher = colder (mountains!)\n- **Oceans** — moderate temperatures nearby\n- **Mountains** — block weather, create rain shadows\n- **Wind patterns** — jet streams and trade winds\n- **Ocean currents** — the Gulf Stream keeps Europe warm\n\nThat's why New York and Seattle — same latitude — have such different climates!

Earth's CLIMATE has always changed slowly. But now it is changing FAST because of human activity.\n\nCAUSES:\n- Burning fossil fuels (coal, oil, gas) releases CO2\n- CO2 traps heat in the atmosphere (greenhouse effect)\n- Cutting down forests (fewer trees to absorb CO2)\n- Factories, cars, power plants\n\nEVIDENCE:\n- Earth's average temperature has risen about 2°F since 1900\n- Ice caps and glaciers are melting\n- Sea levels rising\n- More extreme weather (stronger hurricanes, worse droughts)\n\n97%+ of climate scientists agree: humans are causing this.

Ways to slow climate change:\n\n**INDIVIDUAL**:\n- Use less energy (turn off lights)\n- Walk, bike, or carpool\n- Eat less meat (especially beef)\n- Recycle\n- Plant trees\n\n**SOCIETY**:\n- Switch to renewable energy (solar, wind)\n- Protect forests\n- Make buildings more efficient\n- Electric vehicles\n\nEvery ton of CO2 avoided helps. It's the biggest challenge of your generation.