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Pedro J. Hdez
Attended University of Manchester
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Pedro J. Hdez

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Electricity and energy in the G20

G20 countries obtain only 41.5% of their total energy from electricity and the remaining 58.5% dominantly from oil, coal and gas consumed in the non-electric sector (transportation, industrial processes, heating etc). So even if they eventually succeed in obtaining all their electricity from low-carbon sources they would still be getting more than half their energy from high-carbon sources if no progress is made in decarbonizing their non-electric sectors.
While governments fixate on cutting emissions from the electricity sector, the larger problem of cutting emissions from the non-electricity sector is generally ignored. In this post I present data …
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"This long-term view shows that the next few decades offer a brief window of opportunity to minimize large-scale and potentially catastrophic climate change that will extend longer than the entire history of human civilization thus far."

"Humans have been burning fossil fuels for only about 150 years, yet that has started a cascade of profound changes that at their current pace will still be felt 10,000 years from now."
Raymond Pierrehumbert, a climate scientist and the Halley Professor of Physics at Oxford University.Credit Eva Dalin, Stockholm University
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Climate change in a shoebox: Right result, wrong physic

Classroom experiments that purport to demonstrate the role of carbon dioxide’s far-infrared absorption in global climate change are more subtle than is commonly appreciated. We show, using both experimental results and theoretical analysis, that one such experiment demonstrates an entirely different phenomenon: The greater density of carbon dioxide compared to air reduces heat transfer by suppressing convective mixing with the ambient air. Other related experiments are subject to similar concerns. Argon, which has a density close to that of carbon dioxide but no infrared absorption, provides a valuable experimental control for separating radiative from convective effects. A simple analytical model for estimating the magnitude of the radiative greenhouse effect is presented, and the effect is shown to be very small for most tabletop experiments.
Classroom experiments that purport to demonstrate the role of carbon dioxide’s far-infrared absorption in global climate change are more subtle than is commonly appreciated. We show, using both experimental results and theoretical analysis, that one such experiment demonstrates an entirely different phenomenon: The greater density of carbon dioxide compared to air reduces heat transfer by suppressing convective mixing with the ambient air. Other ...
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There is  no evidence that renewables are having a detectable impact on Germany’s emissions, which have not decreased since 2009 despite a doubling of renewables penetration in the electricity sector. It now seems certain that Germany will miss its 2020 emissions reduction target, quite possibly by a wide margin. In short, the Energiewende is starting to unravel.
Germany is still pursuing its goal of shutting down its nuclear plants but refuses to shut down its lignite plants. It is slashing renewable energy subsidies and replacing them with an auction/quot…
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Positioning exact to the millimeter: Geodetic reference system enables highly accurate positioning https://www.sciencedaily.com/releases/2016/08/160825100943.htm
 
"How many millimeters has the sea level risen? How fast are the continents moving? In order to answer these questions, measurements are being made around the clock at more than 1,700 globally distributed observing stations. These data are then evaluated by researchers. Their new realization of the global reference system that has now been published, is so exact that it even allows to detect seasonal variations".

(Posted by +rasha kamel​)
How many millimeters has the sea level risen? How fast are the continents moving? In order to answer these questions, measurements are being made around the clock at more than 1,700 globally distributed observing stations. These data are then evaluated by researchers. Their new realization of the global reference system that has now been published, is so exact that it even allows to detect seasonal variations.
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Pedro J. Hdez

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Neil deGrasse Tyson y el medallero olímpico: la insoportable superficialidad de un tuit.
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ves esta página sin formato por que esta hecha cumpliendo el estándar web CSS 2. tú navegador no soporta este estándar, o tienes dicho soporte desactivado. si estas en el primer caso, actualízate. merece mucho la pena. Ecos del futuro. Reflexiones sobre ciencia, economía, ecología, ...
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The explosion of atom bombs over the cities of Hiroshima and Nagasaki in August 1945 resulted in very high casualties, both immediate and delayed but also left a large number of survivors who had been exposed to radiation, at levels that could be fairly precisely ascertained. Extensive follow-up of a large cohort of survivors (120,000) and of their offspring (77,000) was initiated in 1947 and continues to this day. In essence, survivors having received 1 Gy irradiation (∼1000 mSV) have a significantly elevated rate of cancer (42% increase) but a limited decrease of longevity (∼1 year), while their offspring show no increased frequency of abnormalities and, so far, no detectable elevation of the mutation rate. Current acceptable exposure levels for the general population and for workers in the nuclear industry have largely been derived from these studies, which have been reported in more than 100 publications. Yet the general public, and indeed most scientists, are unaware of these data: it is widely believed that irradiated survivors suffered a very high cancer burden and dramatically shortened life span, and that their progeny were affected by elevated mutation rates and frequent abnormalities. In this article, I summarize the results and discuss possible reasons for this very striking discrepancy between the facts and general beliefs about this situation.
The explosion of atom bombs over the cities of Hiroshima and Nagasaki in August 1945 resulted in very high casualties, both immediate and delayed but also left a large number of survivors who had been exposed to radiation, at levels that could be fairly precisely ascertained. Extensive follow-up of a large cohort of survivors (120,000) and of their offspring (77,000) was initiated in 1947 and continues to this day. In essence, survivors having re...
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"The mining and milling of Canadian uranium contributes very few greenhouse gases to nuclear power’s already low emissions, a research group has found".
 
"The mining and milling of Canadian uranium contributes very few greenhouse gases to nuclear power’s already low emissions, a research group has found".

(Posted by +rasha kamel​)
The mining and milling of Canadian uranium contributes very few greenhouse gases to nuclear power’s already low emissions, a research group has found.
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A strange thing happened in the stratosphere

"This disruption to the wind pattern - called the "quasi-biennial oscillation" - did not have any immediate impact on weather or climate as we experience it on Earth's surface. But it does raise interesting questions for the NASA scientists who observed it: If a pattern holds for six decades and then suddenly changes, what caused that to happen? Will it happen again? What effects might it have?
"The quasi-biennial oscillation is the stratosphere's Old Faithful," said Paul Newman, Chief Scientist for Earth Sciences at NASA's Goddard Space Flight Center, Greenbelt, Maryland, and lead author on a new paper about the event published online in Geophysical Research Letters. "If Old Faithful stopped for a day, you'd begin to wonder about what was happening under the ground."
Winds in the tropical stratosphere, an atmospheric layer that extends from about 10 to 30 miles above Earth's surface, circulate the planet in alternating easterly and westerly directions over roughly a two-year period. Westerly winds develop at the top of the stratosphere, and gradually descend to the bottom, about 10 miles above the surface while at the same time being replaced by a layer of easterly winds above them. In turn, the easterlies descend and are replaced by westerlies.
This pattern repeats every 28 months. In the 1960s scientists coined it the "quasi-biennial oscillation." The record of these measurements, made by weather balloons released in the tropics at various points around the globe, dates to 1953.
The pattern never changed - until late 2015. As the year came to a close, winds from the west neared the end of their typical descent. The regular pattern held that weaker easterly winds would soon replace them. But then the westerlies appeared to move upwards and block the downward movement of the easterlies. This new pattern held for nearly half a year, and by July 2016 the old regime seemed to resume.
"It's really interesting when nature throws us a curveball," Newman said.
The quasi-biennial oscillation has a wide influence on stratospheric conditions. The amount of ozone at the equator changes by 10 percent between the peaks of the easterly and westerly phases, while the oscillation also has an impact on levels of polar ozone depletion".
 
"This disruption to the wind pattern - called the "quasi-biennial oscillation" - did not have any immediate impact on weather or climate as we experience it on Earth's surface. But it does raise interesting questions for the NASA scientists who observed it: If a pattern holds for six decades and then suddenly changes, what caused that to happen? Will it happen again? What effects might it have?
"The quasi-biennial oscillation is the stratosphere's Old Faithful," said Paul Newman, Chief Scientist for Earth Sciences at NASA's Goddard Space Flight Center, Greenbelt, Maryland, and lead author on a new paper about the event published online in Geophysical Research Letters. "If Old Faithful stopped for a day, you'd begin to wonder about what was happening under the ground."
Winds in the tropical stratosphere, an atmospheric layer that extends from about 10 to 30 miles above Earth's surface, circulate the planet in alternating easterly and westerly directions over roughly a two-year period. Westerly winds develop at the top of the stratosphere, and gradually descend to the bottom, about 10 miles above the surface while at the same time being replaced by a layer of easterly winds above them. In turn, the easterlies descend and are replaced by westerlies.
This pattern repeats every 28 months. In the 1960s scientists coined it the "quasi-biennial oscillation." The record of these measurements, made by weather balloons released in the tropics at various points around the globe, dates to 1953.
The pattern never changed - until late 2015. As the year came to a close, winds from the west neared the end of their typical descent. The regular pattern held that weaker easterly winds would soon replace them. But then the westerlies appeared to move upwards and block the downward movement of the easterlies. This new pattern held for nearly half a year, and by July 2016 the old regime seemed to resume.
"It's really interesting when nature throws us a curveball," Newman said.
The quasi-biennial oscillation has a wide influence on stratospheric conditions. The amount of ozone at the equator changes by 10 percent between the peaks of the easterly and westerly phases, while the oscillation also has an impact on levels of polar ozone depletion".

(Posted by +rasha kamel​)
This disruption to the wind pattern - called the "quasi-biennial oscillation" - did not have any immediate impact on weather or climate as we experience it on Earth's surface. But it does raise interesting questions for the ...
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Pedro J. Hdez

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Climas posibles de Próxima b. Nueva entrada en el blog de climatología donde se estudian algunas características de los posibles climas del exoplaneta recién descubierto en base a modelos sencillos de equilibrio radiativo. El objetivo es mostrar otro ejemplo más de la potencia de los modelos sencillos para ciertos argumentos de tipo general.
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Es una de las noticias científicas del año: el descubierto de un planeta rocoso de una masa parecida a la Tierra que orbita Próxima Centauri a 7,5 millones de kilómetros, con un periodo de traslac…
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Entrada bastante técnica en el blog donde construyo un modelo de equilibrio radiativo multicapa continuo que permite calcular un perfil de temperaturas (poco realista) para la atmósfera, tanto numéricamente (implementado en python en una hoja de SAGE) como analíticamente. El modelo permite de manera sencilla entender varios conceptos fundamentales del transporte radiativo en las atmósferas planetarias que se suelen presentar de manera mucho más abstracta, tal y como  la ley de Beer-Lambert, la profundidad óptica y las ecuaciones de Schwarzchild en la aproximación de dos flujos para una atmósfera plano-pararela, que además permite obtener una solución analítica para el perfil de temperaturas.
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Los modelos tienen muy mala fama, sobre todo en climatología. De hecho se utilizan todo el tiempo como un argumento del tipo “no podemos saberlo”. Es un argumento falaz, porque siendo c…
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10 meses seguidos batiendo el record de temperaturas medias planetarias. La anomalía de la temperatura media del Ártico es mucho más pronunciada, tal y como estaba perfectamente previsto por Hansen et. al. en 1981. Sí, desde hace 35 años teníamos claro lo que iba a ocurrir con el clima... Y está ocurriendo [https://tamino.wordpress.com/2016/08/16/crystal-serenity/]
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"July 2016 was the warmest July in 136 years of modern record-keeping, according to a monthly analysis of global temperatures by scientists at NASA’s Goddard Institute for Space Studies (GISS) in New York.
Because the seasonal temperature cycle peaks in July, it means July 2016 also was warmer than any other month on record. July 2016’s temperature was a statistically small 0.1 degrees Celsius warmer than previous warm Julys in 2015, 2011 and 2009.
“It wasn’t by the widest of margins, but July 2016 was the warmest month since modern record keeping began in 1880,” said GISS Director Gavin Schmidt. “It appears almost a certainty that 2016 also will be the warmest year on record.”
The record warm July continued a streak of 10 consecutive months dating back to October 2015 that have set new monthly high-temperature records. Compared to previous years, the warmer global temperatures last month were most pronounced in the Northern Hemisphere, particularly near the Arctic region.
The monthly analysis by the GISS team is assembled from publicly available data acquired by about 6,300 meteorological stations around the world, ship- and buoy-based instruments measuring sea surface temperature, and Antarctic research stations. The modern global temperature record begins around 1880 because previous observations didn’t cover enough of the planet".

(Posted by +rasha kamel​)
July 2016 was the warmest July in 136 years of modern record-keeping, according to a monthly analysis of global temperatures by scientists at NASA’s Goddard Institute for Space Studies (GISS) in New York.
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Pedro J.'s Collections
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Profesor de tecnología en Secundaria
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Nunca atribuyo a una conspiración aquello que pueda explicarse por simple incompetencia
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Colaborador de naukas.com
Education
  • University of Manchester
    MSc, 1992 - 1993
  • ULL
    Física/Astrofísica, 1986 - 1991
Pedro J. Hdez's +1's are the things they like, agree with, or want to recommend.
El Mundo Today
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La actualidad del mañana.

Porcentual
www.porcentual.es

Ligera subida de la prima de riesgo que supera los 350. La prima de riesgo ha abierto con una ligera subida y supera los 350 puntos básicos,

Udacity
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We believe university-level education can be both high quality and low cost.

AtmosNews
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NCAR + UCAR Science

Google Plus | Novedades y noticias sobre Google plus
www.sologoogleplus.com

Noticias, información, opiniones, aquí podrás encontrar todo lo relacionado con Google plus y sus usuarios.

Está bien saberlo – Google
www.google.com

Utiliza Internet de forma segura. Sugerencias para utilizar Internet con seguridad, incluida información sobre cómo elegir contraseñas segur

Atomic Insights
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Energy for the rest of us

Huérfanos de Diálogos 3
www.msfronteras.org

Huérfanos de Diálogos 3 – Web de antiguos oyentes del programa dirigido por Ramón Trecet – Diálogos 3 – Ramón Trecet – New Age – Folk – Celt

A free and open world depends on a free and open web. | Google
www.google.com

A free and open world depends on a free and open Internet. Governments alone, working behind closed doors, should not direct its future. The

Las células madre inductoras del cáncer
sociedad.elpais.com

La presencia de este material biológico en modelos animales confirma su relación con la enfermedad. El descubrimiento apunta una nueva diana

"Informando" sobre Fukushima
joaquinsevilla.blogspot.com

"Fue un error humano y pudo haberse evitado". Sin duda construir una central nuclear es una decisión humana, y podría haberse decidido lo co

Fukushima and Chernobyl: Myth versus Reality
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Leading experts from the UN Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), the International Commission on Radiological

Inside My Heart... Iona
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Amazing song off of Iona's DVD Live From London... you must buy this DVD!

Nuclear Aftershocks – FRONTLINE
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FRONTLINE travels to three continents to explore the debate about nuclear power: Is it safe? What are the alternatives? And could a Fukushim

Amazings.es
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Ciencia, escepticismo y humor

Creando cantera: el software libre contado a los niños
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Charla presentada en la Libre Software World Conference. Los videos tienen enlaces locales, pero se pueden buscar en Youtube. Habla de nuest

Stream+ for Google+
stream-plus.appspot.com

Stream+ for Google+. The following experiment is just a proof of concept of how to use the Google+ API. Developed by +Mohamed Mansour right

Priceless
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Prada stores carry a few obscenely expensive items in order to boost sales for everything else (which look like bargains in comparison). Peo