the clown wrote:
Nonsense, they're tidal effects predicted entirely by gravitation.Now, here is the correct station pressure data as it is measured all around the world.
First reference.
NATIONAL WEATHER SERVICE DATA:
The most basic change in pressure is the twice daily rise and fall in due to the heating from the sun. Each day, around 4 a.m./p.m. the pressure is at its lowest and near its peak around 10 a.m./p.m. The magnitude of the daily cycle is greatest near the equator decreasing toward the poles.
http://oceanservice.noaa.gov/education/yos/resource/JetStream/atmos/pressure.htmEach day, around 4 a.m./p.m. the pressure is at its lowest and near its peak around 10 a.m./p.m.
Second reference.
GRAPHS SHOWING THE DAILY SEMIDIURNAL BAROMETRIC PRESSURE CHANGES AT 10:00 AM/10:00 PM (MAXIMUMS) AND 4:00 PM/4:00 AM (MINIMUMS):
http://www.geografia.fflch.usp.br/graduacao/apoio/Apoio/Apoio_Elisa/flg0355/textos/Ahrens_cap9.pdf (PG. 211)
Third reference.
A remarkable characteristic of the semi-diurnal barometric variation is the regularity of the occurrence of the maxima and minima and their uniformity in time of day in all latitudes. While the amplitude of these waves may vary greatly with latitude, with elevation, and with location, whether over the sea or over the land, the local times of maxima and minima are very constant.
http://www.archive.org/stream/bulletinobserv06terruoft/bulletinobserv06terruoft_djvu.txt(Bulletin of Applied Physical Science)
A remarkable characteristic of the semi-diurnal barometric variation is the regularity of the occurrence of the maxima and minima and their uniformity in time of day in all latitudes.
ALL LATITUDES, no exception recorded.
EVER.
Fourth reference.
It has been known now for two and a half centuries, that there are more or less daily variations in the height of the barometer, culminating in two maxima and two minima during the course of 24 hours. The same observation has been made and puzzled over at every station at which pressure records were kept and studied, but without success in finding for it the complete physical explanation. In speaking of the diurnal and semidiurnal variations of the barometer, Lord Rayleigh says: ‘The relative magnitude of the latter [semidiurnal variations], as observed at most parts of the earth’s surface, is still a mystery, all the attempted explanations being illusory.
Lord Rayleigh himself did not deny the phenomenon at all: he simply was not able to find an explanation.
Fifth reference.
The atmospheric pressure is greatest at about 10:00 a.m. and 10:00 pm. and least at about 4:00 a.m. and 4:00 p.m. The variations are primarily the result of the combined effects of the sun's gravitational attraction and solar heating, with solar heating being the major component.
http://ufdc.ufl.edu/UF00001262/00001THIS REFERENCE EVEN HAS A GRAPH ATTACHED WHICH DOES SHOW THE 10:00 AM AND 10:00 PM MAXIMUMS (PAGE 569).
The best reference from Soil Engineering.
The atmospheric pressure is greatest at about 10:00 a.m. and 10:00 pm. and least at about 4:00 a.m. and 4:00 p.m.
Sixth reference.
The barometric pressure curve shows a portion of the normal twice-daily oscillation that occurs due to solar and lunar gravitational forces (atmospheric tides), with high pressures at approximately 10:00 AM and PM, and low pressures at 4:00 AM and PM.
http://info.ngwa.org/gwol/pdf/930158405.PDFSeventh reference.
http://www-das.uwyo.edu/~geerts/cwx/notes/chap01/diurnal.htmlSurface pressure measurements in Taiwan (at 25 deg. N) are least around 4am and (especially) 4 pm Local Standard Time, and most around (especially) 10am, and 10pm LST; the amplitude of the semidiurnal cycle is about 1.4 hPa.
Eighth reference.
http://books.google.ro/books?id=vNkZAQAAIAAJ&pg=RA1-PA217&lpg=RA1-PA217&dq=barometer+pressure+semidiurnal+change+10+am+4+pm&source=bl&ots=zgQHfJMC_w&sig=NMbmgLuqwPVwEfGVp3WuSu8Mdgg&hl=ro&sa=X&ei=-As4UqWRL4qp4ATI2ICIBA&ved=0CEAQ6AEwAQ#v=onepage&q=barometer%20pressure%20semidiurnal%20change%2010%20am%204%20pm&f=falseTHIS IS REAL SCIENCE: DAILY SEMIDIURNAL CHANGES IN THE BAROMETER PRESSURE READING.
Maximums at 10:00 am and 10:00 pm, and minimums at 4:00 am and 4:00 pm.
To deny this body of very clear evidence means to leave the realm of science and enter the field of psychiatry.
Ninth reference.
Humboldt carried a barometer with him on his famous South American journeys of 1799-1804. In his book Cosmos he remarked that the two daily maxima at about 10 a.m. and 10 p.m. were so regular that his barometer could serve somewhat as a clock.
http://www-eaps.mit.edu/faculty/lindzen/29_Atmos_Tides.pdfU.S. Weather Bureau, “Ten-Year Normals of Pressure Tendencies and Hourly Station Pressures for the United States,”
Technical Paper No. 1, Washington, D.C. 1943.
Semidiurnal variations: maximums at 10:00 am/10:00 pm and minimums at 4:00 pm/4:00 am
Surface pressure exhibits a remarkably stable semidiurnal oscillation with maxima at 10 a.m. and 10 p.m. and minima at 4 a.m. and 4 p.m. local time. This semidiurnal oscillation in surface pressure is a universal phenomenon observed worldwide and can be identified even in disturbed weather conditions.
http://amselvam.webs.com/SEN1/bio2met.htmREAD CAREFULLY:
NATIONAL WEATHER SERVICE DATA:
The most basic change in pressure is the twice daily rise and fall in due to the heating from the sun. Each day, around 4 a.m./p.m. the pressure is at its lowest and near its peak around 10 a.m./p.m.
A remarkable characteristic of the semi-diurnal barometric variation is the regularity of the occurrence of the maxima and minima and their uniformity in time of day in all latitudes. (Bulletin of Applied Physical Science)
ALL LATITUDES, no exception recorded.Surface pressure exhibits a remarkably stable semidiurnal oscillation with maxima at 10 a.m. and 10 p.m. and minima at 4 a.m. and 4 p.m. local time. This semidiurnal oscillation in surface pressure is a universal phenomenon observed worldwide and can be identified even in disturbed weather conditions.
One maximum is at 10 a.m., the other at 10 p.m.; the two minima are at 4 a.m. and 4 p.m.
The heating effect of the sun can explain neither the time when the maxima appear nor the time of the minima of these semidiurnal variations.
If the pressure becomes lower without the air becoming lighter through a lateral expansion due to heat, this must mean that the same mass of air gravitates with changing force at different hours.Lord Rayleigh: ‘The relative magnitude of the latter [semidiurnal variations], as observed at most parts of the earth’s surface, is still a mystery,
all the attempted explanations being illusory.’
It cannot be explained at all: your vickypedia reference is useless, as it does not address the paradox itself -
One maximum is at 10 a.m., the other at 10 p.m.; the two minima are at 4 a.m. and 4 p.m.
The heating effect of the sun can explain neither the time when the maxima appear nor the time of the minima of these semidiurnal variations.
If the pressure becomes lower without the air becoming lighter through a lateral expansion due to heat, this must mean that the same mass of air gravitates with changing force at different hours.