Thursday, March 25, 2004

Lake Naivasha, Kenya   large images: January 28, 1986 (660 kB JPEG) January 27, 2000 (780 kB JPEG) In southwestern Kenya, northwest of the city of Nairobi, is Lake Naivasha. Naivasha is one of many large and small lakes that occupy eastern Africa’s long Rift Valley, a north-south running depression that has formed where the tectonic plates underlying the continent are pulling away from each other. The freshwater lake is occupies a very dry part of the country, and its presence makes possible an agricultural industry focused on fruits, vegetable, vineyards, and more recently, flower cultivation for world markets. The increasing development of the land surrounding the lake is evident in this pair of images from the Landsat satellite from 1986 (top) and 2000 (bottom). Vegetation appears green, bare ground or low vegetation appears in shades of pink. Urban development appears purple, and water appears deep blue. The increase in the size of the city of Naivasha to the northeast of the lake (at about 2 o'clock) is apparent. New development has sprung up in the south and southeast as well, where bright, reflective rooftops glimmer in the sun. More signs of cultivated land are visible, including the eye-catching, pie-chart shaped fields north of Naivasha (see high-resolution image from 2000). This increase in agricultural development, particularly the flower industry is being blamed by many for a rapid decline in water levels in the lake. The lake also experiences wide year-to-year fluctuations in surface area because it is shallow and highly dependent on rainfall. Indeed, the apparent general decrease in "greenness" around the lake’s perimeter in the 2000 image may be linked to year-to-year variability, since much of the surrounding terrain is less green as well. Images by Jesse Allen, based on data provided by University of Maryland Global Land Cover Facility Recommend this Image to a Friend 7:40:40 PM    comment []

Hewlett-Packard Sues Gateway on Patent Claims By PUI-WING TAM Staff Reporter of THE WALL STREET JOURNAL March 26, 2004 Hewlett-Packard Co. filed a patent-infringement suit against rival Gateway Inc., a move signaling the computer maker's determination to exploit its growing patent portfolio. H-P's suit, filed in federal district court in San Diego late Wednesday, alleges that Gateway infringed six patents that cover a series of computer technologies, including improved password functions and power management. It seeks unspecified damages. H-P is aiming to get "fair compensation from Gateway" for violating the patents, said Joe Beyers, vice president of intellectual-property licensing at H-P, based in Palo Alto, Calif. Bob Sherbin, a Gateway spokesman, said: "The fact is, both companies are in possession of significant patent rights in the area of computer technology. It's premature for them not to take that into consideration before proceeding to a lawsuit. We are very confident of our position and will defend ourselves vigorously." H-P, which holds about 21,000 patents, last year created an intellectual-property licensing group to increase the revenue from that portfolio. The suit against Gateway is the first infringement action this H-P unit has taken since it was created. Mr. Beyers said H-P doesn't want to "lead with litigation" but stressed that "we do need to enforce our rights." H-P is unlikely to press similar suits against other personal-computer makers such as International Business Machines Corp., however. Most of the large PC makers have cross-licensing agreements in place with one another to avoid such legal conflicts, according to Martin Reynolds, an analyst at research firm Gartner. H-P acknowledged that it has licensing agreements with other computer manufacturers, but declined to say which ones. The suit also asks for an injunction to stop Gateway, Poway, Calif., from continuing to ship products that infringe the patents. Mr. Sherbin said stopping shipments of Gateway PCs is "simply not going to happen." H-P's suit stems from a previous licensing agreement that Gateway had with Compaq Computer Corp., which was acquired by H-P in 2002. That agreement expired in 1999 and wasn't renewed. Compaq also had a similar patent licensing agreement with eMachines Inc., which recently was purchased by Gateway. 7:33:13 PM    comment []

Greenhouse gas level hits record high   17:40 22 March 04   NewScientist.com news service   The level of the major greenhouse gas, carbon dioxide, in the Earth's atmosphere has hit a record high, US government scientists have reported. The new data from the US National Oceanic and Atmospheric Administration also suggest that the rate of increase of the gas may have accelerated in the last two years. Carbon dioxide emissions, mainly from burning fossil fuels, are thought to be a principle cause of global warming. Recordings from a volcano-top observatory, NOAA's Mauna Loa Observatory on Hawaii, showed carbon dioxide levels had risen to an average of about 376 parts per million (ppm) for 2003. This is 2.5 ppm up from the average for 2002. It is not the highest leap in year-on-year atmospheric carbon dioxide levels recorded by NOAA. But it is the first to be sustained, with 2002 levels up 2.5 ppm from 2001. This year-on-year hike is considerably larger than the average annual increase of about 1.5 ppm seen over the last few decades says Pieter Tans, chief scientist at NOAA's climate monitoring and diagnostic lab in Boulder, Colorado, US. Other NOAA scientists suggest that economic development in China and India, which leads to increased fuel use, could be a key factor. Year on year "We have been increasing our emissions of greenhouse gases since 1990 and this acceleration is something that we have been aware of and expected," says David Viner, a climate change expert at the University of East Anglia, UK. "It's going to continue to cause profound changes in the climatic system," he told New Scientist. "We are almost already seeing year on year increases in global temperatures." But Brian Hoskins, a member of the UK's Royal Commission on Environmental Pollution, which advises the government, warns that it is not possible to conclude that the rise in carbon dioxide levels has quickened its pace from just one year's figures. "One swallow does not make a summer," he told New Scientist. "We know how much carbon dioxide we are producing and it hasn't changed suddenly over the last year." Tans agrees: "I would be cautious at this point to interpret too much. Yes it's certainly the highest increase in any two-year period we have seen. But to draw conclusions that now we are really into a new trend - that's too early." However, he adds: "Things are steadily going up. Every single month is a new record. I'm not surprised that carbon dioxide levels continue to go up because fossil fuel burning also continues to go up," he told New Scientist. Charles Keeling at the Scripps Institution of Oceanography in San Diego, US, notes that global warming itself could increase the amount of carbon dioxide released from the oceans and soil. "People are worried about feedbacks," he says. Inexorable rise     Subscribe to New Scientist for more news and features   Related Stories   'Pristine' Amazonian rainforests are changing 10 March 2004   Soot worse for global warming than thought 22 December 2003   Global warming's sooty smokescreen revealed 4 May 2003     For more related stories search the print edition Archive     Weblinks   Carbon dioxide measurements, Mauna Loa Observatory   Carbon cycle greenhouse gases, NOAA   Royal Commission on Environmental Pollution, UK   David Viner, Climate impact links project   Intergovernmental Panel on Climate Change     When the US team started recording atmospheric carbon dioxide in the late 1950s, levels were around 315 ppm and have risen ever since. The Intergovernmental Panel on Climate Change projects that, if unchecked, carbon dioxide concentrations in the atmosphere will have risen to between 650 and 970 ppm by 2100. As a result, global temperatures would warm by nearly 6ýC compared with 1990 levels, the IPCC predicts. However, moves to implement the Kyoto Protocol aimed at cutting greenhouse gas emissions have stalled as the US has refused to ratify it, and Russia has not yet made a decision. "This [record level] really shows the importance of the international community tackling climate change," says Viner. "Climate change has stuck its head above the parapet - it's not an issue politicians can hide from much longer."   Shaoni Bhattacharya 7:30:59 PM    comment []

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