Why the hell would Bush care about global warming?...worst case scenario: Ice Caps Melt, Ocean levels rise, California falls into the Ocean, swallowing all the democrats and fairweather republicans that live there. That's a win-win for W if you ask me.
I challenge anyone to write a biography of a boy from the age of 12 to 33 years, who lived 70 years ago, and who'd never been written about before. If you can do that accurately I will allow you to call your book "The Gospel according to [insert your first name here]." Sound familiar?
Anyways, have fun with your stupid little global warming does not exist dream, I need to go sacrifice my first born and beat my wife for talking. The bible tells me so.
how's the milage on those things? when my car is paid for i want to trade in for a prius. also, do they have prius stationwagons?
The mileage is listed as 60 City and 51 Highway....yeah, better in the city. I think that's because breaking produces more energy so when you're stop and go it's building up battery power. In actuallyity though it averages abou 49 mpg overall, which is fantastic. The bullshit numbers that they tell us aren't ever realistic because they're measured at prime mileage speed, usually around 40 mph with no stops. btw, it's not my Prius, it's my sister's....but she drove to the movie when we saw it. In fact since she's had her Prius we always take her car over mine. I'm not as much an environmentalist as I should be, but I'm definitely working on it.
The mileage is listed as 60 City and 51 Highway....yeah, better in the city. I think that's because breaking produces more energy so when you're stop and go it's building up battery power. In actuallyity though it averages abou 49 mpg overall, which is fantastic. The bullshit numbers that they tell us aren't ever realistic because they're measured at prime mileage speed, usually around 40 mph with no stops. btw, it's not my Prius, it's my sister's....but she drove to the movie when we saw it. In fact since she's had her Prius we always take her car over mine. I'm not as much an environmentalist as I should be, but I'm definitely working on it.
well that first part of my post was tounge in cheek, just a little ribbing. i figured you'd be able to handle it.
51 highway, that's great. i'm driving about 50 miles round trip for work everyday. that'd be the shit for me. i'm definitely looking into one.
"PC Load Letter?! What the fuck does that mean?"
~Michael Bolton
“And in my judgment we need to set aside whether or not greenhouse gases have been caused by mankind or because of natural effects and focus on the technologies that will enable us to live better lives and at the same time protect the environment.”
I appreciate his sentiments, but this is a grossly ignorant thing to say.
The greenhouse effect IS natrual. That's scientific fact. It's the name of the process that warms our earth at all.
And it's also fact that we DO produce massive amounts of the gases that make up the greenhouse effect.
Bush needs to do something so he actually understands the issue before he goes after technology.
but i can appreciate what he's doing. I mean.. he clearly has no real knowledge of the issue (based on everything he says about it) but i appreciate that he says he's keeping politics out of it.
And also it seems he's confused politics with science and important information regarding those technologies based on some conservative anti-science dogma.
"Odyssey is giving us indications of recent global climate change in Mars," said Jeffrey Plaut, project scientist for the mission at NASA's Jet Propulsion Laboratory."
Are our SUV's harming Mars also?? Obviously we should've signed Kyoto..save Mars!!!
Why some would be quick to buy global warming on Mars based on barely studied data, yet mock overwhelming solid science on their own planet probably cracks people up also.
Your article is from 2003 and doesn't name an author. Regardless here is an answer from 2005. But as polaris pointed out, this makes no difference. I find it hard to believe you became convinced that every major scientific acadamy was laughably wrong based on data you found from Mars. The summer of 1930 has about the same relevancy.
Nature 435, 184-188 (12 May 2005)
Albedo of the south pole on Mars determined by topographic forcing of atmosphere dynamics
Anthony Colaprete1, Jeffrey R. Barnes2, Robert M. Haberle1, Jeffery L. Hollingsworth3, Hugh H. Kieffer4 and Timothy N. Titus4
The nature of the martian south polar cap has remained enigmatic since the first spacecraft observations1, 2, 3, 4, 5, 6. In particular, the presence of a perennial carbon dioxide ice cap, the formation of a vast area of black 'slab ice' known as the Cryptic region and the asymmetric springtime retreat of the cap have eluded explanation. Here we present observations and climate modelling that indicate the south pole of Mars is characterized by two distinct regional climates that are the result of dynamical forcing by the largest southern impact basins, Argyre and Hellas. The style of surface frost deposition is controlled by these regional climates. In the cold and stormy conditions that exist poleward of 60° S and extend 180° in longitude west from the Mountains of Mitchel ( 30° W), surface frost accumulation is dominated by precipitation. In the opposite hemisphere, the polar atmosphere is relatively warm and clear and frost accumulation is dominated by direct vapour deposition. It is the differences in these deposition styles that determine the cap albedo.
The observed springtime (solar longitude, Ls 200) surface albedo in the martian southern polar region is shown in Fig. 1. The Hellas impact basin is centred at -25° S and 65° W. In general, the hemisphere west of Hellas ('the western hemisphere') is marked by relatively high values of surface albedo. In contrast, the hemisphere east of Hellas ('the eastern hemisphere') contains extensive regions of very low surface albedo. One of the brightest features within the western hemisphere is the south pole residual cap (SPRC). The dark region that dominates the eastern hemisphere is the Cryptic region5.
The nature of the SPRC has been the source of considerable debate since its identification as CO2 ice by the Viking spacecraft. Two fundamental questions still exist regarding the SPRC's formation, location and stability. First, why is the SPRC offset from the geographic pole? There are no local topographic features or surface properties that can account for the offset in the SPRC. Second, does the SPRC represent a large or a small reservoir of CO2? If the former, then it could possibly buffer the surface pressure1. If the latter, then the SPRC may not survive every year.
Just as mysterious as the SPRC is the region of 'black' CO2 ice that dominates the eastern hemisphere (Fig. 1). Known as the Cryptic region5, this area, first observed by Viking and later by Mars Global Surveyor (MGS), becomes visible during the recession of the seasonal cap. The Cryptic region is characterized by its very low visible albedo (< 0.2) and high 25-µm relative emissivity (> 0.95) and is believed to be composed of very clean CO2 'slab' ice. It is the Cryptic region that first sublimes in spring, leading to the observed asymmetric retreat of the southern seasonal cap.
The difference in albedo between the SPRC and the Cryptic region suggests two styles of frost emplacement, and yet, to date, no obvious correlation between topography and surface properties that would favour a SPRC or Cryptic region have been identified5. However, independent observations from MGS indicate that the atmospheric circulation within the polar night produces two distinct climates that encompass the SPRC and the Cryptic region. These observations include cloud echoes from the Mars Orbiter Laser Altimeter (MOLA), ice grain sizes from the Thermal Emission Spectrometer (TES) and temperatures from TES and MGS Radio Science (RS).
This work, using simulations with the NASA Ames Mars General Circulation Model (MGCM), provides a consistent explanation for the various observations and offers a simple interpretation—the topography associated with the Tharsis rise and the Hellas and Argyre impact basins modulates the south polar circulation, producing two distinct climates. Ultimately, the two climates generated by the circulation result in very different surface properties for the CO2 ice cap. Within the hemisphere that includes the SPRC, atmospheric precipitation dominates direct surface deposition, resulting in high albedo frosts; in the Cryptic region, cap ice is accumulated by direct deposition, forming dark CO2 slab ice.
The albedo and emissivity of the polar cap has been associated with the size of the ice grains that make up the surface ice deposits5, 7, 8. Small ice grains result in brighter surfaces, while larger grains result in darker surfaces. A measure of the ice grain size can be derived from differences in the 18-µm and the 25-µm brightness temperatures observed by the TES. The 18-µm brightness temperature is a good measure of the true kinetic temperature, while the 25-µm band is very sensitive to grain size. The 'grain size index' (Fig. 2a) is the difference between the two bands (T18 - T25). Regions with high values of the grain size index include the SPRC and the Mountains of Mitchel. It has been suggested that high grain size indexes are the result of small ice grains in the atmosphere or freshly precipitated to the surface8. MOLA detected cloud echoes within the polar night that have been attributed to the presence of CO2 clouds9, 10, 11. The greatest rates of occurrence are in the western hemisphere. In the eastern hemisphere there are fewer cloud echoes, with a minimum poleward of Hellas basin12.
Also correlating with surface albedos are temperatures derived from TES and RS. Frequently the atmosphere within the polar night chills to below the condensation temperature of CO2 ice and becomes supersaturated. The greatest and most persistent supersaturation, Tsat = Tsat - T, occurs in the western hemisphere and in the longitude corridor of the SPRC (Fig. 2b). Atmospheric temperatures are significantly colder in the western hemisphere compared with the eastern hemisphere. The greatest values of Tsat correlate well with surface brightness and grain size.
It is the atmospheric temperatures that provide insight into what is controlling these two climate regimes. The Tsat for a longitude cut at constant latitude of 75° S is shown in Fig. 2c. Evident in the temperature deviations (Fig. 2b, c) is a low-level planetary wave with a very strong stationary zonal wavenumber-one component. Hinson et al.13 had previously identified this stationary wave in RS and TES observations. The wavenumber-one pattern establishes a low-pressure zone over much of the western hemisphere and a high-pressure zone over much of the eastern hemisphere. This wavenumber-one pattern dominates most of the southern winter, and extends into southern spring (Ls 230). The strong wavenumber-one pattern results in a polar vortex that is offset from the geographic pole and sits over the SPRC.
Furthermore, the amount of variance in atmospheric temperatures is also greatest in the western hemisphere. A distinct 'storm track' exists, starting west of Hellas and extending west past Argyre14. Within this storm track temperatures can vary by as much as 15−20 K per solar day. The rapid decreases in temperature drive the formation of thick clouds and increased precipitation.
To further understand the southern winter dynamics and their association with the SPRC and Cryptic region, several simulations were conducted with the NASA MGCM15. The version of the MGCM used here includes a sophisticated CO2 cloud scheme that predicts cloud formation and precipitation16. Simulations were conducted for a variety of topographic permutations in which the southern extent of Tharsis, Hellas and Argyre were included or removed (Fig. 3).
In the simulation with true (that is, current MOLA observed) topography, temperatures predicted by the model closely match those observed and, in particular, the coldest temperatures are observed in the western hemisphere and encompass the SPRC. Predicted CO2 cloud cover, precipitation and Tsat agree well with the observations described so far (compare Figs 3a and 2b). During the formation of the seasonal cap, cloud cover and precipitation are greatest in a longitude corridor that aligns with the SPRC and are almost completely absent over the Cryptic region. A strong wavenumber-one system dominates from late autumn to mid-winter and establishes a pattern of low and high surface pressures that are consistent with the observations.
When the topography is altered, the regional circulation and, hence, atmospheric temperatures are changed. Figure 3b shows the effect of removing the southernmost extent of the Tharsis rise. Without the southern extent of Tharsis, the hemispherical asymmetry in Tsat, while still evident, is rotated west by about 45° and has somewhat smaller values compared with the case with true topography. If the Hellas and Argyre impact basins are removed (Fig. 3c), the wavenumber-one circulation pattern no longer dominates and cold temperatures occur with much greater symmetry about the pole. A very symmetrical pattern of circulation and cold temperatures results if all topography is removed (Fig. 3d). The simulations indicate that the south polar circulation is controlled by a quasi-stationary planetary (that is, Rossby) wave17 that produces longitudinal variation in the time-mean (for example, seasonal-mean) circulation and climate. The longitudinal asymmetries of the order of 20−30 K seen in the thermal environment between the western and eastern hemispheres in southern high latitudes are a result of this planetary wave that is excited primarily by the planet's middle-latitude surface topography distribution18, 19.
The two climates established by the topographically forced circulation produce differences in the nature of the surface ice deposits. From the MGCM simulations, the relative amounts of CO2 ice that is deposited by precipitation and by direct deposition can be compared. The deposition ratio is defined as the amount of atmospheric precipitation (kg m-2 s-1) divided by the amount of direct surface deposition of CO2 ice. The deposition ratio is area-weighted so that longitude corridors of differing extent can be compared. On average, across the entire polar cap, the deposition ratio is approximately 0.1. However, in some regions the deposition ratio can be as high as 0.9. The greatest deposition ratios occur in the western hemisphere. In the 'true topography' case of the MGCM, the deposition ratio between the longitudes of -135° W and 45° W is 1.56 times as large as the deposition ratio in the opposite hemisphere. If the western edge of this corridor is extended to -180° W, so that the western corridor now extends from -180° W to 45° W, and the eastern hemisphere corridor is confined to just the longitude extent of the Cryptic region, the deposition ratio is 22.4 times as large.
Jakosky and Haberle20 suggested that the SPRC may be unstable from year to year, and that small perturbations in climate may result in the SPRC disappearing some years and reappearing in others. In spring, the recession of the seasonal cap is largely controlled by the surface brightness. Although albedos in local regions on the seasonal cap can change rapidly, the persistent asymmetric circulation creates conditions in which relatively larger grain sizes are stable in the Cryptic region through the sublimation season. Any changes to the circulation can result in changes to the surface brightness and poleward heat flow, and thus modify the recession of the cap. The current SPRC albedo is very close to the minimum required for year-round stability20. If these albedos are only slightly modified by changes in the location or quantity of precipitation, then the SPRC will undergo significant changes and may partially or completely disappear. The observed changes in polar ice features reported by Malin et al.21 and Byrne and Ingersoll22, 23 are consistent with the notion of a SPRC that is only quasi-stable and may undergo significant changes from one year to the next.
The albedo of the south polar ice cap is primarily controlled by the frost grain size. Frost grain size is determined by the style of frost deposition. Smaller grains form when there is atmospheric precipitation to the surface and larger grains form when frost is directly deposited to the surface. Locations that favour one style of frost emplacement over the other are primarily determined by the regional circulation and resulting thermal state. Thus topography, through its influence on the circulation, is ultimately responsible for the nature and location of the SPRC and Cryptic regions on Mars.
one of the most interesting tidbits in gore's movie was the op-ed pieces in the news media ... these PR firms and lobby groups get things published - i'll give them that ... and they for sure have a willing audience who wants to listen ...
its doom and gloom for these people right now ... sure, maybe there would have been this flood but the chances would not have been as high as they are now ...
well that first part of my post was tounge in cheek, just a little ribbing. i figured you'd be able to handle it.
Of course I can handle it, but I do have internal conflict over this because right now I cannot afford a hybrid and the public transportation around here really sucks. I try not to drive a lot and I try to be green in other ways, but I'd kill for a light rail in my area.....not sure what I'd kill, but I'd kill for it.
Why should Bush watch charlatan Gore's propaganda movie?
- read through, we've answered that.
- if by 'propaganda' you mean scientific evidence supporting a theory...
- the problem is much more deep seeded than whether or not the earth is going to have another ice age because of us... we're poisoning our air. If you don't support things like the Kyoto Protocal that anti-global warming nuts HATE, you're a suicidal dumbfuck.
Haven't seen the movie, heard it was a bit light. But somewhere between 50-60% was focused on Gore personally. Self propoganda?
HOB 10.05.2005, E Rutherford 06.03.2006, The Gorge 07.22.2006, Lolla 08.05.2007, West Palm 06.11.2008, Tampa 06.12.2008, Columbia 06.16.2008, EV Memphis 06.20.2009, New Orleans 05.01.2010, Kansas City 05.03.2010
Yeah, but South Park nailed him on that so I don't think we need to worry
Beautiful! Those Southpark boys are going to be in business a long time, there is no lack of material these days.
HOB 10.05.2005, E Rutherford 06.03.2006, The Gorge 07.22.2006, Lolla 08.05.2007, West Palm 06.11.2008, Tampa 06.12.2008, Columbia 06.16.2008, EV Memphis 06.20.2009, New Orleans 05.01.2010, Kansas City 05.03.2010
That's interesting....and I'll consider this and try to do more research on Gore's credibility. Although, we cannot forget that just days ago Bush put USA Today in the category of "small business" http://www.theonion.com/content/node/51352 so I'll have to check the credibility of the source as well. :rolleyes:
Comments
I challenge anyone to write a biography of a boy from the age of 12 to 33 years, who lived 70 years ago, and who'd never been written about before. If you can do that accurately I will allow you to call your book "The Gospel according to [insert your first name here]." Sound familiar?
Anyways, have fun with your stupid little global warming does not exist dream, I need to go sacrifice my first born and beat my wife for talking. The bible tells me so.
aren't you mr. super environmentalist.
how's the milage on those things? when my car is paid for i want to trade in for a prius. also, do they have prius stationwagons?
~Michael Bolton
well that first part of my post was tounge in cheek, just a little ribbing. i figured you'd be able to handle it.
51 highway, that's great. i'm driving about 50 miles round trip for work everyday. that'd be the shit for me. i'm definitely looking into one.
~Michael Bolton
“And in my judgment we need to set aside whether or not greenhouse gases have been caused by mankind or because of natural effects and focus on the technologies that will enable us to live better lives and at the same time protect the environment.”
I appreciate his sentiments, but this is a grossly ignorant thing to say.
The greenhouse effect IS natrual. That's scientific fact. It's the name of the process that warms our earth at all.
And it's also fact that we DO produce massive amounts of the gases that make up the greenhouse effect.
Bush needs to do something so he actually understands the issue before he goes after technology.
but i can appreciate what he's doing. I mean.. he clearly has no real knowledge of the issue (based on everything he says about it) but i appreciate that he says he's keeping politics out of it.
And also it seems he's confused politics with science and important information regarding those technologies based on some conservative anti-science dogma.
http://www.wishlistfoundation.org
Oh my, they dropped the leash.
Morgan Freeman/Clint Eastwood 08' for President!
"Make our day"
Why some would be quick to buy global warming on Mars based on barely studied data, yet mock overwhelming solid science on their own planet probably cracks people up also.
Your article is from 2003 and doesn't name an author. Regardless here is an answer from 2005. But as polaris pointed out, this makes no difference. I find it hard to believe you became convinced that every major scientific acadamy was laughably wrong based on data you found from Mars. The summer of 1930 has about the same relevancy.
Nature 435, 184-188 (12 May 2005)
Albedo of the south pole on Mars determined by topographic forcing of atmosphere dynamics
Anthony Colaprete1, Jeffrey R. Barnes2, Robert M. Haberle1, Jeffery L. Hollingsworth3, Hugh H. Kieffer4 and Timothy N. Titus4
The nature of the martian south polar cap has remained enigmatic since the first spacecraft observations1, 2, 3, 4, 5, 6. In particular, the presence of a perennial carbon dioxide ice cap, the formation of a vast area of black 'slab ice' known as the Cryptic region and the asymmetric springtime retreat of the cap have eluded explanation. Here we present observations and climate modelling that indicate the south pole of Mars is characterized by two distinct regional climates that are the result of dynamical forcing by the largest southern impact basins, Argyre and Hellas. The style of surface frost deposition is controlled by these regional climates. In the cold and stormy conditions that exist poleward of 60° S and extend 180° in longitude west from the Mountains of Mitchel ( 30° W), surface frost accumulation is dominated by precipitation. In the opposite hemisphere, the polar atmosphere is relatively warm and clear and frost accumulation is dominated by direct vapour deposition. It is the differences in these deposition styles that determine the cap albedo.
The observed springtime (solar longitude, Ls 200) surface albedo in the martian southern polar region is shown in Fig. 1. The Hellas impact basin is centred at -25° S and 65° W. In general, the hemisphere west of Hellas ('the western hemisphere') is marked by relatively high values of surface albedo. In contrast, the hemisphere east of Hellas ('the eastern hemisphere') contains extensive regions of very low surface albedo. One of the brightest features within the western hemisphere is the south pole residual cap (SPRC). The dark region that dominates the eastern hemisphere is the Cryptic region5.
The nature of the SPRC has been the source of considerable debate since its identification as CO2 ice by the Viking spacecraft. Two fundamental questions still exist regarding the SPRC's formation, location and stability. First, why is the SPRC offset from the geographic pole? There are no local topographic features or surface properties that can account for the offset in the SPRC. Second, does the SPRC represent a large or a small reservoir of CO2? If the former, then it could possibly buffer the surface pressure1. If the latter, then the SPRC may not survive every year.
Just as mysterious as the SPRC is the region of 'black' CO2 ice that dominates the eastern hemisphere (Fig. 1). Known as the Cryptic region5, this area, first observed by Viking and later by Mars Global Surveyor (MGS), becomes visible during the recession of the seasonal cap. The Cryptic region is characterized by its very low visible albedo (< 0.2) and high 25-µm relative emissivity (> 0.95) and is believed to be composed of very clean CO2 'slab' ice. It is the Cryptic region that first sublimes in spring, leading to the observed asymmetric retreat of the southern seasonal cap.
The difference in albedo between the SPRC and the Cryptic region suggests two styles of frost emplacement, and yet, to date, no obvious correlation between topography and surface properties that would favour a SPRC or Cryptic region have been identified5. However, independent observations from MGS indicate that the atmospheric circulation within the polar night produces two distinct climates that encompass the SPRC and the Cryptic region. These observations include cloud echoes from the Mars Orbiter Laser Altimeter (MOLA), ice grain sizes from the Thermal Emission Spectrometer (TES) and temperatures from TES and MGS Radio Science (RS).
This work, using simulations with the NASA Ames Mars General Circulation Model (MGCM), provides a consistent explanation for the various observations and offers a simple interpretation—the topography associated with the Tharsis rise and the Hellas and Argyre impact basins modulates the south polar circulation, producing two distinct climates. Ultimately, the two climates generated by the circulation result in very different surface properties for the CO2 ice cap. Within the hemisphere that includes the SPRC, atmospheric precipitation dominates direct surface deposition, resulting in high albedo frosts; in the Cryptic region, cap ice is accumulated by direct deposition, forming dark CO2 slab ice.
The albedo and emissivity of the polar cap has been associated with the size of the ice grains that make up the surface ice deposits5, 7, 8. Small ice grains result in brighter surfaces, while larger grains result in darker surfaces. A measure of the ice grain size can be derived from differences in the 18-µm and the 25-µm brightness temperatures observed by the TES. The 18-µm brightness temperature is a good measure of the true kinetic temperature, while the 25-µm band is very sensitive to grain size. The 'grain size index' (Fig. 2a) is the difference between the two bands (T18 - T25). Regions with high values of the grain size index include the SPRC and the Mountains of Mitchel. It has been suggested that high grain size indexes are the result of small ice grains in the atmosphere or freshly precipitated to the surface8. MOLA detected cloud echoes within the polar night that have been attributed to the presence of CO2 clouds9, 10, 11. The greatest rates of occurrence are in the western hemisphere. In the eastern hemisphere there are fewer cloud echoes, with a minimum poleward of Hellas basin12.
Also correlating with surface albedos are temperatures derived from TES and RS. Frequently the atmosphere within the polar night chills to below the condensation temperature of CO2 ice and becomes supersaturated. The greatest and most persistent supersaturation, Tsat = Tsat - T, occurs in the western hemisphere and in the longitude corridor of the SPRC (Fig. 2b). Atmospheric temperatures are significantly colder in the western hemisphere compared with the eastern hemisphere. The greatest values of Tsat correlate well with surface brightness and grain size.
It is the atmospheric temperatures that provide insight into what is controlling these two climate regimes. The Tsat for a longitude cut at constant latitude of 75° S is shown in Fig. 2c. Evident in the temperature deviations (Fig. 2b, c) is a low-level planetary wave with a very strong stationary zonal wavenumber-one component. Hinson et al.13 had previously identified this stationary wave in RS and TES observations. The wavenumber-one pattern establishes a low-pressure zone over much of the western hemisphere and a high-pressure zone over much of the eastern hemisphere. This wavenumber-one pattern dominates most of the southern winter, and extends into southern spring (Ls 230). The strong wavenumber-one pattern results in a polar vortex that is offset from the geographic pole and sits over the SPRC.
Furthermore, the amount of variance in atmospheric temperatures is also greatest in the western hemisphere. A distinct 'storm track' exists, starting west of Hellas and extending west past Argyre14. Within this storm track temperatures can vary by as much as 15−20 K per solar day. The rapid decreases in temperature drive the formation of thick clouds and increased precipitation.
To further understand the southern winter dynamics and their association with the SPRC and Cryptic region, several simulations were conducted with the NASA MGCM15. The version of the MGCM used here includes a sophisticated CO2 cloud scheme that predicts cloud formation and precipitation16. Simulations were conducted for a variety of topographic permutations in which the southern extent of Tharsis, Hellas and Argyre were included or removed (Fig. 3).
In the simulation with true (that is, current MOLA observed) topography, temperatures predicted by the model closely match those observed and, in particular, the coldest temperatures are observed in the western hemisphere and encompass the SPRC. Predicted CO2 cloud cover, precipitation and Tsat agree well with the observations described so far (compare Figs 3a and 2b). During the formation of the seasonal cap, cloud cover and precipitation are greatest in a longitude corridor that aligns with the SPRC and are almost completely absent over the Cryptic region. A strong wavenumber-one system dominates from late autumn to mid-winter and establishes a pattern of low and high surface pressures that are consistent with the observations.
When the topography is altered, the regional circulation and, hence, atmospheric temperatures are changed. Figure 3b shows the effect of removing the southernmost extent of the Tharsis rise. Without the southern extent of Tharsis, the hemispherical asymmetry in Tsat, while still evident, is rotated west by about 45° and has somewhat smaller values compared with the case with true topography. If the Hellas and Argyre impact basins are removed (Fig. 3c), the wavenumber-one circulation pattern no longer dominates and cold temperatures occur with much greater symmetry about the pole. A very symmetrical pattern of circulation and cold temperatures results if all topography is removed (Fig. 3d). The simulations indicate that the south polar circulation is controlled by a quasi-stationary planetary (that is, Rossby) wave17 that produces longitudinal variation in the time-mean (for example, seasonal-mean) circulation and climate. The longitudinal asymmetries of the order of 20−30 K seen in the thermal environment between the western and eastern hemispheres in southern high latitudes are a result of this planetary wave that is excited primarily by the planet's middle-latitude surface topography distribution18, 19.
The two climates established by the topographically forced circulation produce differences in the nature of the surface ice deposits. From the MGCM simulations, the relative amounts of CO2 ice that is deposited by precipitation and by direct deposition can be compared. The deposition ratio is defined as the amount of atmospheric precipitation (kg m-2 s-1) divided by the amount of direct surface deposition of CO2 ice. The deposition ratio is area-weighted so that longitude corridors of differing extent can be compared. On average, across the entire polar cap, the deposition ratio is approximately 0.1. However, in some regions the deposition ratio can be as high as 0.9. The greatest deposition ratios occur in the western hemisphere. In the 'true topography' case of the MGCM, the deposition ratio between the longitudes of -135° W and 45° W is 1.56 times as large as the deposition ratio in the opposite hemisphere. If the western edge of this corridor is extended to -180° W, so that the western corridor now extends from -180° W to 45° W, and the eastern hemisphere corridor is confined to just the longitude extent of the Cryptic region, the deposition ratio is 22.4 times as large.
Jakosky and Haberle20 suggested that the SPRC may be unstable from year to year, and that small perturbations in climate may result in the SPRC disappearing some years and reappearing in others. In spring, the recession of the seasonal cap is largely controlled by the surface brightness. Although albedos in local regions on the seasonal cap can change rapidly, the persistent asymmetric circulation creates conditions in which relatively larger grain sizes are stable in the Cryptic region through the sublimation season. Any changes to the circulation can result in changes to the surface brightness and poleward heat flow, and thus modify the recession of the cap. The current SPRC albedo is very close to the minimum required for year-round stability20. If these albedos are only slightly modified by changes in the location or quantity of precipitation, then the SPRC will undergo significant changes and may partially or completely disappear. The observed changes in polar ice features reported by Malin et al.21 and Byrne and Ingersoll22, 23 are consistent with the notion of a SPRC that is only quasi-stable and may undergo significant changes from one year to the next.
The albedo of the south polar ice cap is primarily controlled by the frost grain size. Frost grain size is determined by the style of frost deposition. Smaller grains form when there is atmospheric precipitation to the surface and larger grains form when frost is directly deposited to the surface. Locations that favour one style of frost emplacement over the other are primarily determined by the regional circulation and resulting thermal state. Thus topography, through its influence on the circulation, is ultimately responsible for the nature and location of the SPRC and Cryptic regions on Mars.
http://news.yahoo.com/s/nm/20060809/sc_nm/weather_india_dc_3
George Washington
- if by 'propaganda' you mean scientific evidence supporting a theory...
- the problem is much more deep seeded than whether or not the earth is going to have another ice age because of us... we're poisoning our air. If you don't support things like the Kyoto Protocal that anti-global warming nuts HATE, you're a suicidal dumbfuck.
http://www.wishlistfoundation.org
Oh my, they dropped the leash.
Morgan Freeman/Clint Eastwood 08' for President!
"Make our day"
http://www.wishlistfoundation.org
Oh my, they dropped the leash.
Morgan Freeman/Clint Eastwood 08' for President!
"Make our day"
Beautiful! Those Southpark boys are going to be in business a long time, there is no lack of material these days.
http://www.wishlistfoundation.org
Oh my, they dropped the leash.
Morgan Freeman/Clint Eastwood 08' for President!
"Make our day"
http://www.usatoday.com/news/opinion/editorials/2006-08-09-gore-green_x.htm
- 8/28/98
- 9/2/00
- 4/28/03, 5/3/03, 7/3/03, 7/5/03, 7/6/03, 7/9/03, 7/11/03, 7/12/03, 7/14/03
- 9/28/04, 9/29/04, 10/1/04, 10/2/04
- 9/11/05, 9/12/05, 9/13/05, 9/30/05, 10/1/05, 10/3/05
- 5/12/06, 5/13/06, 5/27/06, 5/28/06, 5/30/06, 6/1/06, 6/3/06, 6/23/06, 7/22/06, 7/23/06, 12/2/06, 12/9/06
- 8/2/07, 8/5/07
- 6/19/08, 6/20/08, 6/22/08, 6/24/08, 6/25/08, 6/27/08, 6/28/08, 6/30/08, 7/1/08
- 8/23/09, 8/24/09, 9/21/09, 9/22/09, 10/27/09, 10/28/09, 10/30/09, 10/31/09
- 5/15/10, 5/17/10, 5/18/10, 5/20/10, 5/21/10, 10/23/10, 10/24/10
- 9/11/11, 9/12/11
- 10/18/13, 10/21/13, 10/22/13, 11/30/13, 12/4/13