Global Climate Change Chapter 1

Introduction

earth’s a finite and fragile resource, earth’s climate can be studied using the systems approach, evolves over time due to its own internal dynamics and due to external forcings (volcanic eruptions, solar variations, human actions), balanced incoming and outgoing radiation cause a stable global climate, unbalanced incoming and outgoing radiation cause a climate shift to gain/lose energy, earth isn’t in a global radiative equilibrium (system gaining energy, climate change is taking place), establishes environmental conditions and sets boundaries for weather, climate is dynamic with changing in the past and change in the future, consequences grow in number/intensity based on past/current human actions

Climate

state of a complex system consisting of 5 major components and their interactions

5 components

atmosphere, hydrosphere, cryosphere, lithosphere, biosphere

System

arbitrary portion of the universe with fixed/movable boundaries which may contain matter, energy, or both

What are the scales that climate occurs on varying in magnitude and direction?

natural cycles, and human actions

Climate studies for human endeavors

climate is variable but changing at unprecedented rate due to the burning of fossil fuels, human activities link humans to the earth’s natural systems making climate change more complex, mitigation, greenhouse gases, adaptation, climate change heightens the vulnerabilities of societies and ecosystems, impact both global and local with economic interdependence enhances the global component

Mitigation

actions that reduce sources of gases which contribute to the warming of the climate system and enhance the mechanisms that removes them from the atmosphere

Greenhouse gases

gases that contribute to the warming of the climate system

Adaptation

adjustment in natural/human systems to actual/expected climatic stimuli/their effects, moderates harm/exploits beneficial opportunities

Climate variability

change in average state of the climate on all spatial and temporal scales separate from singular weather events, occurs with/without human actions

Climate change

change in the state of the climate system, identified by changes in the average conditions and the variability of its properties, persists for an extended period, typically decades/longer due to natural/anthropogenic processes and forcings

Climate vulnerability

degree to which physical, biological, and socioeconomic systems are susceptible to/incapable of coping with adverse impacts of a variation in climate

Example of climate vulnerability

Katrina and Sandy have proven that modern society isn’t shielded from climate-induced social degradation

Sustainability

capacity to meet the needs of the present without compromising the ability of future generations meet their own needs, balancing mitigation attempts with economic impacts can cause resistance

Changing climate

east of the last 3 decades has been warmer at the surface than any preceding decade since 1850, ocean is warming more than any other location (much of this energy is likely stored in the deep ocean), plant and animal species also react to changes, ecosystem

Ecosystem

collection of living organisms within the nonliving substances they depend on/near the surface of the Earth (changes in the climate affect ecosystems in many ways, significant ecosystems disturbance signals a change in the climate system

Climate variability vs change

variability relates to natural fluctuations on a smaller time scale, range of variation and change are a response to the interactions of many mechanisms, differentiating between the 2 is done by mathcing causes to a forcing agent

Peer Review Process

objective, professional evaluation of scientific studies and published papers, ensures data and findings are accurate and accurately reported, ensures a high level of credibility and quality

Current climate paradigm

climate change 1st reported in the 1980s, we must look at all components and sub-systems and interactions, climatology, climate science, scientific method

Climatology

scientific discipline that investigates earth’s climate system, focusing on how it functions, what drives it changes, how it varies in both space and time, empirical and theoretical

Climate science

scientific discipline generally focusing more on the physical processes on earth that can affect/force climate to change

Scientific method

process entailing systematic observation, measurement, experimentation, formation, testing, and modification of hypotheses, used as a template for scientific investigations

Modes by which climate is defined

climate is more encompassing and enduring than weather, atmosphere is a continuum with energy and mass being exchanged constantly, use weather variables and observations over long periods of time to get a glimpse at climate

Climate system

climatologists look at each of the subsystems to pose hypotheses about how it will operate in the future, open system, closed system

Open system

system that exchanges both energy and mass with its environment

Closed system

system that exchanges energy but not mass with its environment

Atmosphere

free-flowing, well-mixes, envelope of gases at the interface of earth and space, necessary for survival of life on earth, nitrogen, oxygen, and water vapor, trace gases, studied by temperature profile, broken into layers based upon the lapse rate, troposphere, ozone, stratosphere, mesosphere, thermosphere, warming in 1 later can cause cooling in another, as troposphere warms the stratosphere cools

Lapse rate

changes in temperature with height

Trace gases

atmospheric gases with much smaller concentrations, often making up less than a hundredth/thousandth percent of the atmosphere, yet still have a significant impact on the climate system

Troposphere

interacts with other spheres and sub-systems as it is the lowest later of the atmosphere

Ozone

alters the thermal profile 20-30 km above the surface, variant of oxygen, triatomic molecule that’s 3 oxygen atoms rather than 2 in the most common form of oxygen, and highly concentrated in the stratosphere, serves as a protective barrier against UV radiation

Stratosphere

2nd lowest layer of the atmosphere, major temperature inversion and an underlying isothermal (ozone shield)

Mesosphere

2nd highest layer of the atmosphere

Thermosphere

highest layer of the atmosphere with a temperature inversion, where gases absorb highly energetic solar radiation

Hydrosphere

all water in all forms on, under and over earth’s surface, covers more than 2/3 of the planet, occurs naturally in all 3 states of matter, changes in state can have a dramatic impact on climate, 96.5 of water is in the ocean, 68 of remaining freshwater is ice, remainder of freshwater is in groundwater, lakes, etc, less than 1% of water exists in the vapor phase, closed system but is dynamic with movement caused by changes in temperature and salinity

Cryosphere

portion of the hydrosphere in solid form, ice is found in the polar regions, east antarctic ice sheet seem to be unaffected but it’s believed wind direction is helping to save this ice sheet from melting, continued warming will cause melting of ice sheets and decrease glacial volumes, 23% of N hemisphere covered in ice during winter months, annual cycles of snow and ice are monitored because they serve as a signal for climate change, volume as well as physical properties with albedo are measured

Lithosphere

relatively cool, crusty, outer layer encompassing earth’s surface to the deeper, hotter portions where rocks become more elastic and melt (upper mantle), crust is thinnest under the oceans and thickest under continents, houses a great abundance of resources that are used by fuels, asthenosphere, broken into large plates that move over the period of millions of years

Asthenosphere

layers of rock below the lithosphere that bend more like a fluid and adjust to stress through plastic-like deformations

Hot spots

volcanic activity can occur on the plate boundaries/at hot sports, occurs when super heated materials rise in plumes from below, coincide with a plate boundary (Iceland)

Pedosphere

portion of the lithosphere at its upper-most extent that forms the world’s soils, all organisms in the soils, water flows through cracks and permeated deep into the lithosphere, freeze thaw cycle can trap greenhouse gases

Biosphere

integrates all living beings and their relationships with the lithosphere, hydrosphere, cryosphere, and atmosphere, collection of all ecosystems worldwide, every part of earth supports life of some sort, broken into produces, consumers and decomposers, food chain, food web

Food chain

relationship between consumers and decomposers

Food web

consists of all the food chains in a single ecosystem

Koppen

recognized the climatic influence on ecosystems, developed a climate scheme based upon native vegetation in the area, sign of temperature and precipitation patterns in the area

Carbon cycle

ties all subsystems together, chemically/physically transformed between spheres due to the law of conservation of matter, carbon moving through living entities, non-living entities (rocks) in the form on a myriad of compounds, part of a biogeochemical cycle, conservation of matter, fossil fuels

Conservation of matter

matter can be neither created nor destroyed, but can change in chemical/physical form, which are released through the burning of fossil fuels by adding carbon dioxide to atmosphere at greater rates

Fossil fuel

coal, oil, gas that formed from the layering and compression of organic sediment

Mass deposition

made during carboniferous period