MODULE 3: THE ATMOSPHERIC ENVIRONMENT
Lecture 13, Week 7
INTRODUCTION TO THE ATMOSPHERIC ENVIRONMENT
Lecture Outline:
• Weather and climate
• The atmospheric environment is important
• A few introductory concepts
WEATHER AND CLIMATE
What is climate science?
• Atmospheric Science Meteorology Climatology
• Deals with the dynamics of the entire atmosphere–ocean–land surface climate system, in terms of its
internal interactions and its response to external factors, for example, incoming solar radiation.
WEATHER AND CLIMATE
Weather
• The state of the atmosphere, mainly with respect to its effects upon life and human activities.
• As distinguished from climate, weather consists of the short-term (minutes to days) variations in the
atmosphere.
• Popularly, weather is thought of in terms of temperature, humidity, precipitation, cloudiness, visibility, and
wind.
Climate
• The slowly varying aspects of the atmosphere – hydrosphere – land surface system
• It is typically characterised in terms of suitable averages of the climate system over periods of. Month or
more, taking into consideration the variability in time of these averaged quantities. Climatic classifications
include the spatial variation of these time-averaged variables
• Beginning with the view of local climate as little more than the annual course of long-term averages of surface
temperature and prediction, the concept of climate has broadened and evolved in recent decades in response
to the increased understanding of the underlying process that determine climate and its variability
,THE ATMOSPHERIC ENVIRONMENT IS IMPORTANT
The Atmospheric Environment
• In it right now
• We spend our lives surrounded by it
• It impacts every aspect of our lives
• Think of all the web sites in the world. The 35th most visited web site by Australians is the Australian Bureau
of Meteorology web site: bom.gov.au
• Important for our health and wellbeing
THE ATMOSPHERIC ENVIRONMENT CAN KILL
Thunderstorm Asthma (Melbourne, November 2016)
• The Epidemic Thunderstorm Asthma Event resulted from the interaction of the thunderstorm with extreme
levels of airborne grass pollen.
• Exposed people in Melbourne to an extremely high dose of rye grass pollen allergen.
• Within 30 hours there were:
o 3365 (672%) excess respiratory-related presentations to emergency departments
o 476 (992%) excess asthma-related admissions to hospital
o 35 individuals admitted to an intensive care unit.
• The Victorian Coroner found that there were 10 deaths directly attributable to the event.
WHAT IS THE MOST COMMON GAS IN OUR ATMOSPHERE?
• The most abundant naturally occurring gas is Nitrogen (N2), which makes up 78% of air.
• Oxygen (O2) is the second most abundant gas at approx. 21%
SCALES OF ATMOSPHERIC PHENOMENA
• Time and space scales of various atmospheric phenomena. The shaded area represents the characteristic
domain of boundary layer features.
o E.g., Meso-scale atmospheric phenomena have a characteristic horizontal distance scale of 10km to
200km.
THE CLIMATE SYSTEM
• Five “spheres”
o Atmosphere
o Hydrosphere
o Biosphere
o Cryosphere
o Geosphere
• Processes and interactions. Change and variability
, Lecture 14, Week 7
ATMOSPHERIC ENERGY AND THE STRUCTURE OF THE ATMOSPHERE
Lecture Outline:
• Radiation in the Atmospheric Environment
• Daily and Seasonal Variability
• The Energy Balance
RADIATION IN THE ATMOSPHERIC ENVIRONMENT
• Radiation from the Sun is by far the major source of energy in the climate system.
• Radiation from the Sun is the most important driver of climates near the ground.
RADIATION
• Solar energy gets to Earth by Electromagnetic Radiation
• Different types of waves
• Can characterise a wave by the distance and trough
• Amplitude: half the distance between trough and peak
SOME SYMBOLS AND UNITS
• Wavelength is measured in micrometres (μm)
- μ is Greek small letter mu
- 1 μm = 1 million of a metre
• The symbol for wavelength is λ
- Greek small letter lambda
• The units for radiation and energy in the climate system are Joules per second per square metre
• A Joule per second is a Watt (W), Wm-2
RADIATION EMISSION AND ABSORPTION
• All objects emit radiation
• The nature of radiation is dependent on temperatures
• Shows the distribution of wavelength emitted by the sun and Earth
Lecture 13, Week 7
INTRODUCTION TO THE ATMOSPHERIC ENVIRONMENT
Lecture Outline:
• Weather and climate
• The atmospheric environment is important
• A few introductory concepts
WEATHER AND CLIMATE
What is climate science?
• Atmospheric Science Meteorology Climatology
• Deals with the dynamics of the entire atmosphere–ocean–land surface climate system, in terms of its
internal interactions and its response to external factors, for example, incoming solar radiation.
WEATHER AND CLIMATE
Weather
• The state of the atmosphere, mainly with respect to its effects upon life and human activities.
• As distinguished from climate, weather consists of the short-term (minutes to days) variations in the
atmosphere.
• Popularly, weather is thought of in terms of temperature, humidity, precipitation, cloudiness, visibility, and
wind.
Climate
• The slowly varying aspects of the atmosphere – hydrosphere – land surface system
• It is typically characterised in terms of suitable averages of the climate system over periods of. Month or
more, taking into consideration the variability in time of these averaged quantities. Climatic classifications
include the spatial variation of these time-averaged variables
• Beginning with the view of local climate as little more than the annual course of long-term averages of surface
temperature and prediction, the concept of climate has broadened and evolved in recent decades in response
to the increased understanding of the underlying process that determine climate and its variability
,THE ATMOSPHERIC ENVIRONMENT IS IMPORTANT
The Atmospheric Environment
• In it right now
• We spend our lives surrounded by it
• It impacts every aspect of our lives
• Think of all the web sites in the world. The 35th most visited web site by Australians is the Australian Bureau
of Meteorology web site: bom.gov.au
• Important for our health and wellbeing
THE ATMOSPHERIC ENVIRONMENT CAN KILL
Thunderstorm Asthma (Melbourne, November 2016)
• The Epidemic Thunderstorm Asthma Event resulted from the interaction of the thunderstorm with extreme
levels of airborne grass pollen.
• Exposed people in Melbourne to an extremely high dose of rye grass pollen allergen.
• Within 30 hours there were:
o 3365 (672%) excess respiratory-related presentations to emergency departments
o 476 (992%) excess asthma-related admissions to hospital
o 35 individuals admitted to an intensive care unit.
• The Victorian Coroner found that there were 10 deaths directly attributable to the event.
WHAT IS THE MOST COMMON GAS IN OUR ATMOSPHERE?
• The most abundant naturally occurring gas is Nitrogen (N2), which makes up 78% of air.
• Oxygen (O2) is the second most abundant gas at approx. 21%
SCALES OF ATMOSPHERIC PHENOMENA
• Time and space scales of various atmospheric phenomena. The shaded area represents the characteristic
domain of boundary layer features.
o E.g., Meso-scale atmospheric phenomena have a characteristic horizontal distance scale of 10km to
200km.
THE CLIMATE SYSTEM
• Five “spheres”
o Atmosphere
o Hydrosphere
o Biosphere
o Cryosphere
o Geosphere
• Processes and interactions. Change and variability
, Lecture 14, Week 7
ATMOSPHERIC ENERGY AND THE STRUCTURE OF THE ATMOSPHERE
Lecture Outline:
• Radiation in the Atmospheric Environment
• Daily and Seasonal Variability
• The Energy Balance
RADIATION IN THE ATMOSPHERIC ENVIRONMENT
• Radiation from the Sun is by far the major source of energy in the climate system.
• Radiation from the Sun is the most important driver of climates near the ground.
RADIATION
• Solar energy gets to Earth by Electromagnetic Radiation
• Different types of waves
• Can characterise a wave by the distance and trough
• Amplitude: half the distance between trough and peak
SOME SYMBOLS AND UNITS
• Wavelength is measured in micrometres (μm)
- μ is Greek small letter mu
- 1 μm = 1 million of a metre
• The symbol for wavelength is λ
- Greek small letter lambda
• The units for radiation and energy in the climate system are Joules per second per square metre
• A Joule per second is a Watt (W), Wm-2
RADIATION EMISSION AND ABSORPTION
• All objects emit radiation
• The nature of radiation is dependent on temperatures
• Shows the distribution of wavelength emitted by the sun and Earth
