2 Flashcards
- What is thought to be the principle source of water on Earth?
The ocean is the immediate source of water on Earth. Earth was once a dry rocky mass, but
now its surface is 71% water. The source of this water is believed to be from asteroids and
meteorites that impacted Earth.
The chief source of Earth’s early atmosphere was outgassing. Explain what is meant by
outgassing. Does outgassing still operate today?
a. Outgassing refers to the release of gases (e.g., water vapor, nitrogen) to the atmosphere that
accompanies a volcanic eruption or meteor impact on Earth’s surface. Outgassing was one of the
major processes involved in the evolution of Earth’s atmosphere. While outgassing occurred at a
rapid pace within a million years of the planet’s formation, a small amount of outgassing still
takes place today.
Explain how living organisms played an important role in the evolution of Earth’s atmosphere.
a. Living organisms played a large role in Earth’s atmosphere, primarily through photosynthesis.
Oxygen is a byproduct of photosynthesis and became abundant in the atmosphere about 2.3
billion years ago.
Distinguish between the homosphere and the heterosphere.
The homosphere is the area of the atmosphere below 80 km in which the principal gases are
well mixed and in almost the same relative same proportions. Above 80 km lies the heterosphere
where the concentrations of heavier gases decrease more rapidly with altitude than do the
concentrations of the lighter gases.
The significance of an atmospheric gas or aerosol is not necessarily related to its amount or
concentration. Explain this statement and provide a few examples.
The principal gases in the homosphere are nitrogen and oxygen and are significant and
essential, however other gases and aerosols in small quantities are significant constituents.
Water vapor, carbon dioxide, and ozone are minor components of the atmosphere. Water vapor
is an essential component of the water cycle and is the major greenhouse gas in the atmosphere.
Carbon dioxide is necessary for photosynthesis. Ozone formation and dissociation in the
stratosphere shields living organisms on Earth’s surface from exposure to potentially lethal levels
of solar ultraviolet radiation.
Distinguish among the various types of scientific models used in meteorology and
climatology.
a. Atmospheric scientists use physical models to create small scale replications of a system, graphical models (e.g., weather maps) to represent the state of the atmosphere at a specific time and geographical area, conceptual models to portray the interaction of atmospheric variables such as wind, temperature and pressure, and numerical models that use mathematical equations describing the Earth-atmosphere system to forecast the weather and climate.
What are the components of ASOS and where is the observational data initially sent?
a. The Automated Surface Observing System (ASOS) consists of electronic sensors for
measurements, computers, and automated communications ports. ASOS directly feeds data to
NWS communications networks 24 hours a day to Forecast Offices and airport control towers
What is the principal mission of the National Weather Service Cooperative Observer
Network?
a. The NWS Cooperative Observer Network is made up of approximately 8,700 volunteers that
monitor NWS provided instruments and take daily observations. Their mission is to record data
for climatic, hydrologic, and agricultural purposes.
What is a radiosonde? Describe the function served by a radiosonde launch.
a. A radiosonde provides vertical profiles (soundings) of temperature, pressure, and dewpoint (a
measure of humidity) up to a maximum altitude of about 30,000 m (100,000 ft). Data are
radioed immediately to a ground station and no recovery of an instrument is required. Tracking
the instrument’s horizontal movements gives a vertical profile of the horizontal wind speed and
direction (rawinsonde observation).
Compare the properties of the troposphere with those of the stratosphere.
a. Most cloud and weather systems are confined to the troposphere and within the troposphere
the temperature generally decreases with increasing altitude. Few clouds and little weather occur
in the stratosphere. Within the stratosphere the mean temperature is either steady or increases
with altitude. Also, the ozone shield occurs within the stratosphere. The tropopause is the
transition zone or boundary between the troposphere and the stratosphere
Solar radiational heating of the Earth-atmosphere system is balanced by emission of heat to space in the form of infrared radiation
Global radiative equilibrium
What is the calendar effect?
Theory that global climate change can be brought about by enhancement of Earth’s natural greenhouse effect by increased levels of atmospheric CO2 from anthropogenic sources
What are some impacts of global warming?
climate zones may shift poleward -Heat and moisture stress would cut crop production in certain areas
Possible farming at higher latitudes.
Rising sea levels of 20-60 cm (8-24 in.) during the 21st century
Inundation of low islands and coastal plains
Many are heavily populated
Decreased snow cover and sea-ice extent
Actions that should be taken to head off possible enhanced green house warming
Sharply reduce oil and coal consumption
Have greater reliance on non-fossil fuel energy sources
Have higher energy efficiencies
Halt to deforestation, massive reforestation
Even if it were not for enhanced greenhouse warming, doing this would help other problem areas
Example: cutting air pollution
What does a pyranometer measure ?
the intensity of solar radiation that strikes a surface
