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POPSPuffing the great wind scam What is dangerous is that even contemplating such a mad waste of resources is diverting attention from the genuine need to build enough proper, grown-up power stations to keep our lights on. For that the time is fast running out, if it hasn't done so already
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POPSFresh water lakes in the heart of the Sahara Desert The reason for the apparent paradox—fresh water lakes in the heart of the desert—is that fresh water from a very large aquifer reaches the surface in the Ounianga Depression. The aquifer is large enough to keep supplying the small lakes with water despite the high evaporation rate. Mats of floating reeds also reduce the evaporation in places. The lakes form a hydrological system that is unique in the Sahara Desert. The aquifer was charged with fresh water and the original lake evolved during the African Humid Period (about 14,800 to 5,500 years ago), when the West African summer monsoon was stronger than it is today. Associated southerly winds brought Atlantic moisture well north of modern limits, producing sufficient rainfall in the central Sahara to foster an almost complete savanna vegetation cover.
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POPSGiant Crack in Africa Will Create a New Ocean The thinking is that the Red Sea will eventually pour into the new sea in a million years or so. The new ocean would connect to the Red Sea and the Gulf of Aden, an arm of the Arabian Sea between Yemen on the Arabian Peninsula and Somalia in eastern Africa.
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POPSAn Open Letter to the Council of the American Physical Society Studies of a variety of natural processes, including ocean cycles and solar variability, indicate that they can account for variations in the Earth’s climate on the time scale of decades and centuries. Current climate models appear insufficiently reliable to properly account for natural and anthropogenic contributions to past climate change, much less project future climate. The APS supports an objective scientific effort to understand the effects of all processes – natural and human --on the Earth’s climate and the biosphere’s response to climate change, and promotes technological options for meeting challenges of future climate changes, regardless of cause. List of 160 signers of the APS petition available
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POPSglobal temperature variations are dictated by ENSO Observations indicate that global temperature rise has slowed in the last decade. The least squares trend for January 1999 to December 2008 calculated from the HadCRUT3 dataset (Brohan et al. 2006) is +0.07±0.07°C decade–1—much less than the 0.18°C decade–1 recorded between 1979 and 2005. El Niño–Southern Oscillation is a strong driver of interannual global mean temperature variations. ENSO and non-ENSO ontributions can be separated by the method of Thompson et al. The trend in the ENSO-related component for 1999–2008 is +0.08±0.07°C decade–1, fully accounting for the overall observed trend. The trend after removing ENSO (the "ENSO-adjusted" trend) is 0.00°±0.05°C decade–1, implying much greater disagreement with anticipated global temperature rise.
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POPSChannels associated with impact craters discovered on Mars If a significant amount of water was released or mobilized by the formation of the Hale Crater impact, larger impacts that formed during the early days of the Solar System may have been able to bring even more water to the surface of Mars. If this is true, a long-term, stable, warm and wet climate may not be required to explain the presence of such channels in the ancient Martian landscapes.
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POPSCapitan Reef Over millions of years, segments of the Capitan Reef were uplifted, and much of the sediment was eroded away from the more resistant limestone reef materials. The Guadalupe Mountains, stretching to the northeast from El Capitan in Texas to near Carlsbad, New Mexico, are one of these uplifted portions of the reef. The southern end of the range is included within Guadalupe Mountains National Park. As this uplift continued, groundwater that supported some of the material in many of the caverns drained away, and material collapsed to form large underground chambers, such as those in Carlsbad Caverns National Park. Because the reef was built, in large part, through the accumulation of dead marine organisms that incorporated calcium carbonate into their structures, fossils are abundant in the reef deposits throughout the exposed portions of the Guadalupe Mountains.
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POPSLong Exposure - (5 sec rule of thumb) "The scene: A place with a crowd of people, or a view with moving traffic, or a landscape with running or moving water. Dim lighting, or twilight/dusk, is best." "The equipment: A camera that allows you to manually set the exposure time, a tripod if appropriate for the location (otherwise, a way to hold the camera completely still), and a remote shutter release or timer (hands-off shutter firing)."
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