GREENHOUSE EFFECT

Lakukan tugas rumah & ujian kamu dengan baik sekarang menggunakan Quizwiz!

Terrestrial Radiation: Introducing the Greenhouse Effec

A. If earth's climate is unchanging then incoming energy must be balanced by outgoing radiation. That outgoing radiation is Terrestrial Radiation, also known as long wave or infrared radiation BUT ... NOT all terrestrial radiation goes back into space B. Counterradiation 1. Carbon dioxide (CO2), water vapor and a few other gases in atmosphere absorb some of the terrestrial radiation emitted by Earth and re-direct it back to surface. 2. So extra source of heat for earth 3. CO2 and water vapor (and a few other gases) act as thermal blanket for earth - trapping heat 4. Counterradiation concept is best known as GREENHOUSE EFFECT

Pumping liquid CO2 into the bottom of the ocean.

Federal energy officials have joined scientists worldwide in studying the disposal of carbon dioxide as a way of slowing down the "greenhouse effect." The U.S. Department of Energy has funded two carbon "sequestration" programs — one on land and one in the deep ocean — for $9 million. Since 1999, it funded another $18 million in research grants. Scientists are just now beginning to examine the disposal of carbon dioxide, one of the primary greenhouse gases linked to global warming. The idea is to get rid of carbon dioxide from factories, cars and other sources of fossil fuel burning before the odorless gas reaches the atmosphere.

: if we can evaluate the evidence scientifically and establish the levels of uncertainty associated with it, can we then apply a climate philosophy (such as promoted by groups like the oil/gas companies or by groups like Greenpeace) in determining future policies?

Oddly enough, that question raises the question of faith. How much uncertainty in our climate predictions are you personally—regardless of your scientific training—willing to accept?

OCEAN IRON FERTILIZATION

Of all climate engineering proposals, fertilization of the Southern Ocean with iron has raised the most controversy. The idea has been around for about 20 years, and is credited to John Martin who first developed the clean laboratory techniques to measure how little iron there was dissolved in open seawater: During the 1993 Iron Enrichment Experiment (IRONEX), researchers dumped iron into a 64-square-kilometer area and measured the resulting phytoplankton bloom.

L. F. Richardson and the numerical prediction of weather

Richardson said that "All major atmospheric processes could be defined into five... equations. These equations expressed the factors and interrelationships controlling atmospheric temperature, pressure, density (the so-called "state" variables of the atmosphere) and derived atmospheric variables such as wind (north/south, meridional; east-west, zonal; up-down, vertical) and moisture." Five variables = five equations: mathematics says that they can be solved precisely (closure)

BRANCH ONE: the Modelers

Simple Climate Model: Change in Temperature with Time = f(radiation, storage and energy flows) The very first climate model was created in 1968 - this model treated the entire world as a single point and based on sunshine and heat loss through terrestrial radiation, calculated the earth's temperature. ... Climate models rapidly became more sophisticated—dividing the world into grids and computing weather at those grid points. The first detailed "General Circulation Model" or GCM was created as part of the CLIMAP project in the 1970s What goes into a model? A General Circulation Model is constructed on the five basic so-called "primitive equations" of motion. 1. "equation of state" 1. pressure 2. 1st law of thermodynamics 2. temperature 3. equation of mass continuity 3. density 4. equation of moisture continuity 4. moisture 5. Navier-Stokes equation of motion 5. wind Closure: a set of equations can be solved if you have the same # of variables as you have equations 1975: After CLIMAP, scientists went back home and began to create a whole series of GCMs ... General Circulation Models NCAR CCM (GCM): Community Climate MOdel GISS: Goddard Institute for Space Studies GFDL: Geophysical Fluid Dynamics Laboratory OSU: Oregon State Model (CLIMAP model) ECCM: European Community Climate Model Start of CO2 experiments but major emphasis in 1970s: response of earth to a reduction in solar constant of 1% (remember future ICE AGES were the big concern) Bulk loading models. Although differing dramatically, GCMs all show consistent warming with CO2 increases. The magnitude of the predicted global average warming generally lay between 4 and 10°C for a CO2 doubling. Most of the model show the largest temperature increase occurring in the polar or subpolar regions. For comparison, Last Ice Age estimates 4°C reduction of global temperature and for Cretaceous 8°C increase from modern values. Early 1980s, the National Academy of Sciences and the Environmental Protection Agency release reports discussing catastrophic climate changes resulting from projected CO2 warming. Early 80s models indicated an 8-10ºF increase in temperature in 30 years - sealevel would rise 10-50 meters 1988: Massive heat wave in the east. Jim Hansen, director of Goddard Institute of Space Studies, called to testify before congress. "99% sure that global warming is occurring." based his statement on results of his climate model Yellowstone Fires Hurricane Gilbert Empirists versus the Modelers (Phase 1) Sherwood Idso (Biologist): took on modeling "Thought experiments" ... CO2 can be good ...discredited by modeling climatologists.

So what does this all mean?

So, in my opinion, if you want to assess the future of our climate, here are some questions you might want to consider when evaluating a new piece of evidence (for example, a story, interview or expose on climate change): a) What are the data? b) Do the data or analyses generally match past observations or analyses? c) Do the researchers profess a philosophy prior to presenting the evidence? BUT a scientific analysis should be as free as possible from the possible biases (conscious or subconscious) associated with that philosophy.

climate engineering proposals

Stix (1989) suggested that Infrared Lasers could be used to dissociate CFC's in the lower atmosphere to retard their flow into the stratosphere (where chlorine form CFC's destroys ozone). Cicerone et al. (1991) introduced the idea of suppressing the the annual destruction of zone in the Antarctic polar stratosphere by injecting ethane or propane. But Elliott et al.(1994) shows that reactions could lead to greater problems Can we cool the earth? It has been suggested that we could deliberately inject either sulfate aerosols or dust into the stratosphere (like a human volcano) The idea is first credited to the Soviet scientist Budyko (1974) and developed by many others since, mainly in the US, even reaching a US government report (National Academy of Sciences 1992). Originally rockets or rifle shells would have carried the dust, but Penner (1984) suggested that it could be done more easily by a slight modification of commercial jet fuel, and this would be very cheap. In a policy statement to an International Energy Workshop in San Diego in 1992, Penner presented the dust idea as a "Low-cost no regrets" option for mitigating greenhouse warming, showing that it would cost just 0.1 cents (using coal dust) to cool the planet to compensate for one ton of Carbon as CO2 in the atmosphere, or 1 cent if SiH4 was used to make inert SiO2 dust (Penner 1993). Solar radiation might also be deliberately reflected locally by altering the surface "albedo". There have even been discussions about "painting the deserts white". Can we make the world "better" People have always dreamed of greening the world's deserts. Their potential as a CO2 sink as well as a food source has revived interest in such grand schemes. One such proposal from the Japan Gas Association and RITE (Ozawa et al 1995) includes generation of clouds by evapotranspiration from coastal mangroves and lagoons, and artificial mountains to promote rainfall, along with underground dams and new cities

Denver TV News: Did Utah Olympic Cloud Seeding Causing Colorado Drought?

That project was nicknamed STORMFURY. Its purpose: to modify hurricanes through cloudseeding . The idea was that seeding hurricanes with silver iodide (AgI) crystals would reduce wind strength -- in essence, rain a hurricane out before it could become dangerous. The argument was that seeding the band of convective clouds just outside the eye wall would trigger additional latent heat release and would enhance convection. A new eye wall would form at a greater radius from the storm center -- and just like an ice skater's rotation rate slows when the arms are extended, so would the hurricanes. In 1963, shortly after hurricane Beulah was seeded with silver iodide, surface pressures in the eye began to rise and the region of maximum winds moved away from the storm's center. In 1969, after seeding Hurricane Debbie, a 30% reduction of wind speed was noted. But the question remains,would the winds have been lower naturally? The inconclusive results, plus fears of "bad modifications" and a lack of "modifiable" hurricanes, eventually caused the project to be abandoned. Recently: Dyn-O-Gel is a special powder (produced by Dyn-O-Mat) that absorbs large amounts of moisture and then becomes a gooey gel. It has been proposed to drop large amounts of the substance into the clouds of a hurricane to dissipate some of the clouds thus helping to weaken or destroy the hurricane. At Hurricane Research Dynamics researchers tried the one possible way that "Dyn-O-Gel" could weaken a hurricane in the MM5 numerical model. They saw an effect but it was small (~1 m/s). Two big problems: you need A LOT of it to have any effect ... and then what happens to it after the hurricane?

Mintz-Arakawa Circulation Model, sometimes called the CLIMAP Model.

The first climate that incorporated all the stuff of the weather models No matter what it is called, it was the first GENERAL CIRCULATION MODEL or GCM

how big of an effect will the greenhouse effect be and how long will it last?

The second question is easier to answer: At best estimates, fossil fuels will run out in 300 years - consequently the greenhouse effect will cease to be a major factor some time after that. The first question, "How big will be the effect" is the tougher one. Scientists continue to study, model and argue about the long-term effects. AT PRESENT, scientists anticipate warming of 2° to 4°C by the end of this century. The lower estimate would likely have only limited impact to the Southwest. Most scientists have concentrated on the problem of sea-level rise associated with global warming - areas currently near sea level made experience more flooding and storm damage as global warming continues. The wild card with the upper estimate is this odd possibility: Global Warming leading to a new ice age An increasing number of scientists are concerned with the possibility that global warming might create instability in the Antarctica ice sheet, causing part of the ice sheet to slide into the southern oceans. Such a slide would lead to a massive abrupt cooling of the southern oceans. That would severely modify the global weather patterns - and conceivably we might be in an ice age within a few short years! Is it likely? Well, scientists now are studying how unstable Antarctica is. So in summary: over the next century, temperatures are likely to be warmer (more frequent 120s and definitely hotter night temperatures), but the likelihood is that the factors we are facing today (e.g., El Niño, the Pacific Decadal Oscillation, Volcanoes and Urban Climate Change) are still going to be the main factors to face over the next 100 years. The Next Millennium (2013 -3013)

The original CLIMAP GCM had

an ocean 1/2" deep gave us a "snapshot" of the climate had a resolution of 4 degrees latitude x 5 degrees longitude

M.I. Budyko and William Sellers of Uof Arizona

developed a different idea for climate models ... they worked with the ENERGY BALANCE For a non-changing climate: Incoming sunlight = Outgoing Terrestrial Heat BUT ... then climate modelers did what the weather modelers did: Add more things into the model

climate isn't day-to-day

it refers to long periods of weather so weather models didn't seem to be the best basis for climate models

The key to realize is that climate modeling is a TOOL

like a weather balloon or a thermometer. It has its good points and it has its bad points. No matter how good or bad the models, models are being used to study climate ... and those studies now include the ability to CHANGE climate - what has been called "climate engineering" or more frequently "geoengineering"

Cloudseeding

the basic idea of cloudseeding used today is simply to inject particles into the air that act as condensation nuclei -- the tiny little material that water will condense around. Cloudseeding can not occur in clear skies. The best conditions are when the top of the cloud is cold -- in other words, the top of the cloud has supercooled water in it. Working of the General Electric Laboratories, Schaefer & Irving dropped crushed pellets of dry ice (solid carbon dioxide) from a plane. The extreme cold of dry air (~ 78°C or -108°F) causes some of the supercooled water droplets to freeze and begin to grow by absorption of more supercooled water. In 1947, Bernard Vonnegut demonstrated that silver iodide (AgI) was a better cloudseeding agent than dry air. The atomic structure of silver iodide is similar to that of ice and, consequently, it acts as a condensation nucleus around which supercooled water can collect. The advantages of silver iodide: 1. much easier to handle than dry ice 2. It can be spread easier -- using burners located on either the ground or more likely from the wind of small aircraft. But how effective is cloudseeding? This is a very hard question to answer simply because we don't know exactly how much rain would have occurred had there NOT been any cloudseeding ... Under optimum conditions, cloudseeding may enhance precipitation by at most maybe 20 percent. The problem is that cloudseeding is almost an art as well as a science -- over-seeding can produce too many ice crystals. This leads to an over- abundance of ice crystals in ratio to the amount of supercooled water and the ice particles don't grow large enough to fall as precipitation. Eventually, these ice crystals evaporate leaving a clear patch of sky. In of the earlier cloudseeding attempts, researchers created the logo of GE in the top of a status cloud.

100,000 years into the future A.D. 2013 to A.D. 103012 SUMMARY

• Over the next decade the Southwest should be slightly warmer, perhaps drier than now, and have less of a difference between high and low temperatures. • Over the next century, temperatures are likely to be warmer, but present-day forces (e.g., ENSO, PDO, volcanoes, urbanization) are still going to be the main factors. • Ice ages are headed our way far into the future... Please remember, though ... Climatology is a VERY young science - only about 30 years old or so - so take everything I just said with a large grain of salt.

the father of the computer, John Von Neumann

, and two meteorologists used the first numerical computer, ENIAC, to make a 24-hour weather forecast

The difference between a greenhouse and the greenhouse effect

1. A "greenhouse" is a building that allows sunlight in to heat up the earth and then traps that heated air within the building. (Nothing to do with infrared radiation) 2. The "greenhouse effect" is the effect produced by carbon dioxide and water vapor (and a few other gases) to trap the earth's heat (infrared radiation) close to the earth.

BRANCH TWO: The empirists

1950: Hurd Willet begins an attempt to organize all available surface temperature record: mainly western Europe and U.S. Project continued by Mitchell (1961) and Reitan (1974). 1982: Climate Analysis Center: University of East Anglia: P.D. Jones, P.M. Kelly and T.M.L. Wigley produce a global record of temperature. conclusion: temperature has risen 0.45°C ± 0.15°C in last century. worldwide recession of mountain glaciers. Warming apparently occurred over both land and oceans. Tom Karl of NCDC and R.C. Balling of ASU both independently examine the possible biases associated with available datasets a. Competing effects: continental versus ocean the urban heat island changes in cloud cover movement of thermometers accuracy of recording devices 1986: Southern Hemispheric dataset (Jones and his group) much cleaner trends ... upward trend since turn of century ... rise of 0.5°C 1988-89: Research indicates that decade of 1980s was very warm, particularly in Southern Hemisphere. Heat wave in 1988 in Eastern U.S. Media attention. 1990-1993: Cooling (Mt. Pentubo and sustained El Niño) Persian Gulf War I briefly shifts attention to oil fires and "nuclear winter" The satellite dataset: In the 90s, Christy and Spenser of NASA decided to use the orbiting NOAA satellites that measure Infrared Temperatures (IR) - the heat measured by the surface of the earth This is the global temperatures determined by the global satellite record up to 1998 The satellite record appeared to show little to no warming while the Jones et al. surface record showed large warming Big problem The battleground was set Modelers versus Empirists: Phase 2 - work together! IPCC: Intergovernmental Panel on Climate Change 1990 Second report at 1992, revised 3th in 2001, 4th in 2007: "Most of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations." What is the Intergovernmental Panel on Climate Change IPCC? An international group loosely linked to the United Nations and the World Meteorological Organization. Presently "2500 scientists" but ... of that 2500, only 400 are climatologists and of that 400 only 130 are associated with actual document writing of reports, of that 130 only a handful (10-20) may be associated with the policy decision making. The IPCC reports have generated three distinct reactions: 1. Scientific merits of research 2. Political ramifications of research 3. Funding considerations of research And over the last decade, a third major dataset has entered the fray: The third big 'global warming' dataset: the radiosonde (weather balloon record): from 1957 to present So by turn of the millennium: three big temperature datasets: the surface record, the satellite record, the radiosonde record: all show warming But now the climate reconstructionists get back into the picture Hockey stick controversy They suggest that the warming we are seeing in the last 100 years is unlike anything we have seen in last 1000 years - lots of debate on quality of data!!! Then Politics starts to enter ... Politicians begin to fund and support the scientists based on political considerations. Greenhouse warming has become not only a scientific problem - it is also a political problem. It has been linked to political movements—BOTH pro & con (e.g., environmental and industrial)—who have vested interest in finding and promoting evidence to support their viewpoints BUT actually, that helps create good science—the more evidence we find, the better our understanding of climate change. Science should ALWAYS involve challenging the accepted! -but unfortunately the reverse also holds true - and that is NOT good for Science Two scientists on completely opposite sides of the political spectrum—both friends of mine—have been forced into not speaking publicly because their scientific views countered the political administrations at the time: James Hansen was forced quiet by the Bush/Cheney administration while Sherwood Idso was forced quiet by the Clinton/Gore administration Climategate began in November 2009 with the hacking of an email server at the Climatic Research Unit (CRU) at the University of East Anglia (UEA) Again, I'm not taking political sides but the politicialization of short-term (e.g., decades) climate change has become pronounced and we MUST be concerned about the quality of science when it becomes politized! Results can be forced to reflect political view Lack of temperature increase in the 2000s: "flattening" of curve "Greenhouse Advocates" point to the last decade as the hottest in the last 100 years "Greenhouse Deniers" point to temperatures not raising as they had been doing So should we be worried? The IPCC projects a temperature rise of 2-4˚C by the end of the century, depending on different emission scenarios ... Is that enough to be worried about? Guess what? I don't know the answer!

Greenhouse gases

: water vapor, carbon dioxide, methane, nitrous gases, chloroflurocarbons E. Is the Greenhouse Effect Real? We have measured the amount of greenhouse gases in our atmosphere: QUITE DEFINITELY, THE AMOUNT OF GREENHOUSE GASES IS INCREASING. Therefore, according to theory, the globe should be warming. How Much? Once again, the problem point is feedbacks Early 80s models indicated an 8-10ºF increase in temperature in 30 years Seasonal biospheric response: In Spring (northern hemisphere),biosphere expands, taking up CO2 faster than decay and respiration can give it back In fall and winter, respiration and decay exceed photosynthesis and CO2 builds up in atmosphere 1970s: Most scientists were studying the question of a new global ice age; particularly after the severe winter of 1976-1977 With media attention: Climatology Flourished! The discipline broke into two distinct branches with little interaction:


Set pelajaran terkait

Chapter 22 - Disorders of Hemostasis, Chapter 23 - Disorders of Red Blood Cells, Chapter 26 - Disorders of Blood Flow, Chapter 26 - Disorders of Blood Pressure Regulation, Chapter 27 - Disorders of Cardiac Function, Chapter 27 - Heart failure and Cir...

View Set

Accounting Fundamentals Sessions 7-13

View Set

Linux Chapter 1, Linux Test chapters 4-9

View Set

Intro to Computer Science Quizes

View Set

MKT 300: Chapter 16: Retailing and Omnichannel Marketing

View Set

Calculation of maintenance fluids

View Set

Chapter 27: Lower Respiratory Problems

View Set

Pharm Ch 3: Toxic Effects of Drugs

View Set

Chapter 35: Assessment of Immune Function

View Set