Changing Global Temperatures and Climate Observations

• Atmospheric carbon dioxide levels have spiked above 300 parts per million due to the industrial revolution and anthropogenic contributions
• Increased carbon dioxide and other greenhouse gases enhance the natural greenhouse effect, leading to more infrared energy being re-emitted back to the atmosphere, causing warming above natural levels
• Temperature anomalies have been increasing since 1940, with 2019 being the second warmest year on record globally, with temperatures 2.07 degrees Fahrenheit above pre-industrial levels
• Ocean temperatures have been rising, with 2019 having the highest ever total ocean heat content throughout the global oceans
• The polar vortex is an upper-level low-pressure area over the poles with very cold air swirling around it, weakening in summer and strengthening in winter, influencing weather patterns
• A weaker jet stream due to warming can cause the polar vortex to fracture, leading to cold air seeping southward and affecting regions like the United States
• Melting ice due to polar warming can slow down the thermohaline circulation, impacting global climate by affecting water density and circulation patterns
• A ZONAL JET STREAM means the vortex is locked up in the polar region. Zonal simply means "not wavy". No meanders in the jet stream.
• Natural causes of climate change:

  • Plate tectonics: About 300 million years ago, a supercontinent called Pangaea existed, causing extreme cold and glacial climates in certain regions before the continents shifted to their current positions
  • Variation in solar energy reaching Earth based on changes in Earth's orbital parameters:
  • Eccentricity: Changes in Earth's orbit shape on 100,000-year cycles
  • Obliquity: Variations in the angle of Earth's tilt on a 41,000-year cycle
  • Precession: Wobbling of Earth's axis on a 23,000-year cycle
• • Volcanic eruptions: Eject fine particles of ash and dust into the stratosphere, leading to cooling effects due to reflective sulfuric acid particles and haze
  • Variations in solar output: Sunspots, magnetic storms on the sun's surface, impact solar output variations every 11 years
• Climate feedbacks:

  • Positive feedback: Amplifies initial changes, such as melting ice reducing reflectivity, leading to increased absorption of solar radiation and further warming
  • Negative feedback: Dampens initial changes, such as increased atmospheric water vapor causing more cloud formation, reflecting incoming solar energy and causing a decrease in temperature
• Climate modeling:

  • Climate models use mathematical equations to simulate present and future climate, accounting for various factors like ocean-atmosphere interactions, changes in carbon dioxide concentrations, cooling effects of sulfate particles, and climate feedbacks
  • Climate models differ from weather forecasting models by providing projections weeks to years in advance
  • The Intergovernmental Panel on Climate Change (IPCC) was created in 1988 to conduct research on climate change and produces assessments every seven years, with the most recent being the fifth assessment in 2014
• • IPCC projections show a wide range of global surface temperature anomalies based on different greenhouse gas concentration scenarios, with potential temperature increases up to four degrees Celsius above normal by 2100
• Modes of observing climate include satellites, buoys, radiosondes, and surface weather stations
• Radiosondes provide temperature, humidity, wind speed and direction, atmospheric pressure, and other metrics at different levels of the atmosphere, especially within the troposphere
• Surface weather stations measure important weather variables such as rain, temperature, dew point, precipitation type, wind speed and direction, and more
• Buoys and ships measure ocean variables like temperature, salinity, and other ocean properties
• NOAA has a network of buoys focused on current weather and general research
• NOAA also uses aircraft, like hurricane hunter aircraft, to observe extreme conditions in hurricanes
• Satellites provide information about weather, clouds, winds, temperatures, and precipitation from above the surface
• NOAA has polar orbiting and geostationary satellites for weather observations
• Visible satellites look at cloud types, infrared satellites measure cloud top temperatures, and water vapor satellites measure atmospheric moisture
• NOAA synthesizes surface and satellite observations to produce weather maps and forecasts
• NOAA's Advanced Weather Interactive Processing Systems (AWIPS) combine data from satellites, radar, and surface observations to draw up surface weather maps and produce forecasts
• The Chesapeake Bay Interpretive Buoy System is a network of 10 buoys collecting real-time meteorological, oceanographic, and water quality data
• The buoys in the Chesapeake Bay system have components like anemometers, temperature humidity sensors, solar panels, wave measurement systems, water quality monitors, and more
• Argo is a buoy network in the southern oceans with over 3,800 operational floats providing data at depths of several kilometers deep
• NASA's satellite oceanography observes currents, eddies, biological productivity, sea level changes, waves, sea surface temperatures, and air-sea interactions
• The Argo observational network measures observations from


  space