Atmosphere, Weather, and Climate

• To describe weather, one could measure wind speed, wind direction, precipitation, clouds, and temperature.
• Weather describes atmospheric conditions, like wind and rain, at a specific time, while climate describes typical seasonal conditions.
• Climate is influenced by ocean currents, the Sun’s energy, and global wind patterns.
• Climates generally get cooler when moving north away from the equator.
• A hydrologist studies the distribution and movement of Earth’s water.
• Being near an ocean moderates temperature changes, resulting in cooler summers and warmer winters, and can also affect precipitation.
• Weather forecasts are difficult to extend beyond a week or two due to the constant changes in numerous influencing factors.
• Meteorologists provide probabilities in forecasts due to the inherent uncertainties in predicting weather.

Atmosphere

• The atmosphere is mainly composed of gases like nitrogen, oxygen, argon, and water vapor.
• Temperatures and pressure in the atmosphere vary with altitude.
• An anemometer measures wind speed.

Water

• Deepwater ocean currents are mainly caused by differences in water density due to variations in temperature and salt concentrations.
• Most of Earth’s water is in oceans.
• 71% of Earth’s surface is covered in water.
• Ocean currents affect climate by moving heat around the Earth, with some currents carrying heat from the equator to northern regions, thus warming those areas.

Climate Change

• A major factor in current global warming is the burning of fossil fuels.
• Human activities contribute to rising surface temperatures by releasing greenhouse gases, such as carbon dioxide, into the atmosphere through the burning of fossil fuels.
• Greenhouse gases trap thermal energy near the Earth's surface, leading to a temperature increase.