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Tuesday, 24 June 2008

New climate model and new type of memory chip

My comments are after the articles, as always :) I particularly much enjoy the new type of memory chip. It sounds utterly awesome...

In a New Climate Model, Short-Term Cooling in a Warmer World

Published: May 1, 2008

After decades of research that sought, and found, evidence of a human influence on the earth’s climate, climatologists are beginning to shift to a new and similarly daunting enterprise: creating decade-long forecasts for climate, just as meteorologists routinely generate weeklong forecasts for weather.

One of the first attempts to look ahead a decade, using computer simulations and measurements of ocean temperatures, predicts a slight cooling of Europe and North America, probably related to shifting currents and patterns in the oceans.

The team that generated the forecast, whose members come from two German ocean and climate research centers, acknowledged that it was a preliminary effort. But in a short paper published in the May 1 issue of the journal Nature, they said their modeling method was able to reasonably replicate climate patterns in those regions in recent decades, providing some confidence in their prediction for the next one.

The authors stressed that the pause in warming represented only a temporary blunting of the centuries of rising temperatures that scientists have projected if carbon dioxide and other heat-trapping gases continue accumulating in the atmosphere.

“We’re learning that internal climate variability is important and can mask the effects of human-induced global change,” said the paper’s lead author, Noel Keenlyside of the Leibniz Institute of Marine Sciences in Kiel, Germany.

The new study focused on relationships between short-term climate trends and a system of currents in the Atlantic Ocean, called the meridional overturning circulation, which undergo periodic changes. The predictions were made by repeatedly running a simulation of the global climate and adjusting conditions in the simulated oceans to match temperature measurements.

To get a computer-generated simulation of the climate for the 1990s, for example, the model ran from the 1950s through the 1980s, with sea temperatures adjusted to reflect the real world, then ran without further inputs for 10 more years.

The model is a rough replica of conditions, the scientists said. While it reliably reproduced climate patterns in Europe and North America, the model could not replicate patterns over central Africa, for example.

In e-mail exchanges, several climate experts not associated with the study expressed a variety of views on the new cooling forecast. But they agreed that the work served the important function of at least trying to chart what will assuredly be a winding climatic journey toward a generally warmer world.

Other researchers, including NASA scientists at the Jet Propulsion Laboratory in Pasadena, Calif., reported separately on April 21 that a slowly fluctuating oscillation in Pacific Ocean temperatures had shifted into its cool phase, a condition that is also thought to exert an overall temporary cooling of the climate.

“Too many think global warming means monotonic relentless warming everywhere year after year,” Dr. Trenberth said. “It does not happen that way.” source

My comment: First, please notice the authors are German. I noticed it, because in the moment Germany is desperately trying to get its energy intensive industry to avoid CO2 emission regulations. Which may or may not be connected with the article.

Second, I think they might be right, though I don't know to what extent. And third, the article doesn't imply people should stop worrying about Global Warming as it was presented by some news channels. It merely says climate is much more complicated than we think.

H.P. Reports Big Advance in Memory Chip Design

Published: May 1, 2008

Hewlett-Packard scientists reported Wednesday in the science journal Nature that they have designed a simple circuit element that they believe will make it possible to build tiny powerful computers that could imitate biological functions.

The device, called a memristor, would be used to build extremely dense computer memory chips that use far less power than today’s DRAM memory chips. Manufacturers of today’s chips are rapidly reaching the limit on how much smaller chips can be.

The memristor, an electrical resistor with memory properties, may also make it possible to fashion advanced logic circuits, a class of reprogrammable chips known as field programmable gate arrays, that are widely used for rapid prototyping of new circuits and for custom-made chips that need to be manufactured quickly.

Potentially even more tantalizing is the ability of the memristors to store and retrieve a vast array of intermediate values, not just the binary 1s and 0s conventional chips use. This allows them to function like biological synapses and makes them ideal for many artificial intelligence applications ranging from machine vision to understanding speech.

Independent researchers said that it seemed likely that the memristor might relatively quickly be applied in computer memories, but that other applications could be more challenging. Typically, technology advances are not adopted unless they offer large advantages in cost or performance over the technologies they are replacing.

The original theoretical work done by Mr. Chua was laid out in a paper, “Memristor — The Missing Circuit Element.” The paper argued that basic electronic theory required that in addition to the three basic circuit elements — resistors, capacitors and inductors — a fourth element should exist.

The Hewlett-Packard researchers said that the discovery of the memory properties in tiny, extremely thin spots of titanium dioxide came from a frustrating decade-long hunt for a new class of organic molecules to serve as nano-sized switches. Researchers in both industry and academia have hoped they would be able to fashion switches as small as the size of a single molecule to someday replace transistors once the semiconductor industry’s shrinking of electronic circuits made with photolithographic techniques reached a technological limit.

The memristor is a radically different approach from another type of solid state storage called phase-change memory that is being pursued by I.B.M., Intel and other companies. In phase-change memory, heat is used to shift a glassy material from an amorphous to a crystalline state and back again. The switching speed of these systems is both slower and requires more power, according to the Hewlett-Packard scientists.

The Hewlett-Packard team has successfully created working circuits based on memristors that are as small as 15 nanometers (the diameter of an atom is roughly about a tenth of a nanometer.) Ultimately, it will be possible to make memristors as small as about four nanometers, Mr. Williams said. In contrast the smallest components in today’s semiconductors are 45 nanometers, and the industry currently does not see a way to shrink those devices below about 20 nanometers.

The most significant limitation that the Hewlett-Packard researchers said the new technology faces is that the memristors function at about one-tenth the speed of today’s DRAM memory cells. They can be made in the same kinds of semiconductor factories that the chip industry now uses, however.

source

My comment: If that's not cool, I don't know what is. This is progress in action and the very reason behind my blog. To be able to report such great moments in history. I'm very happy that it was a big company that discovered that new chip, because now we know, they'll do what they can to implement it and thus get the money the invested back and promote it. Which mean new technologies, new smaller and faster computers and more money in science. Lovely!

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