Home Tags Posts tagged with "national oceanic and atmospheric administration"
national oceanic and atmospheric administration
Carbon dioxide levels in the atmosphere have broken through a symbolic mark reaching its highest throughout human history, recent figures from a US monitoring station show.
Daily measurements of CO2 at a US government agency lab on Hawaii have topped 400 parts per million (ppm) for the first time.
The station, which sits on the Mauna Loa volcano, feeds its numbers into a continuous record of the concentration of the gas stretching back to 1958.
The last time CO2 was regularly above 400 ppm was three to five million years ago – before modern humans existed.
Scientists say the climate back then was also considerably warmer than it is today.
Carbon dioxide is regarded as the most important of the manmade greenhouse gases blamed for raising the temperature on the planet over recent decades.
Human sources come principally from the burning of fossil fuels such as coal, oil and gas.
The usual trend seen at the volcano is for the CO2 concentration to rise in winter months and then to fall back as the northern hemisphere growing season kicks in. Forests and other vegetation pull some of the gas out of the atmosphere.
Carbon dioxide levels in the atmosphere have broken through a symbolic mark reaching its highest throughout human history
This means the number can be expected to decline by a few ppm below 400 in the coming weeks. But the long-term trend is upwards.
James Butler is responsible for the Earth System Research Laboratory, a facility on Mauna Loa belonging to the National Oceanic and Atmospheric Administration (NOAA). Its daily average CO2 concentration figure on Thursday was 400.03.
He said: “Carbon dioxide has some variability on an hourly, daily and weekly basis, so we are not comfortable calling a single number – the lowest we will go is on a daily average, which has happened in this case.
“Mauna Loa and the South Pole observatory are iconic sites as they have been taking CO2 measurements in real time since 1958. Last year, for the first time, all Arctic sites reached 400 ppm.
“This is the first time the daily average has passed 400 ppm at Mauna Loa.”
The long-term measurements at Mauna Loa were started by a Scripps Institution of Oceanography scientist called Charles Keeling.
In 1958, he found the concentration at the top of the volcano to be around 315 ppm (that is 315 molecules of CO2 for every one million molecules in the air). Every year since then, the “Keeling Curve”, as it has become known, has squiggled resolutely higher.
Scripps still operates equipment alongside NOAA on the mountain peak.
Its readings have been pushing 400ppm in recent days, and on Thursday recorded a daily average of 399.73.
But NOAA senior scientist Pieter Tans said: “Our measurements [NOAA] are in Coordinated Universal Time, while the Keeling measurements are in local Hawaii time. If you shift the Keeling definition of a day to the same as ours then we do agree almost completely on the measurements.”
By this definition, the Keeling team’s Thursday number would be 400.08 ppm.
And Dr. James Butler added: “Probably next year, or the year after that, the average yearly reading will pass 400 ppm.
“A couple of years after that, the South Pole will have readings of 400 ppm, and in eight to nine years we will probably have seen the last CO2 reading under 400 ppm.”
To determine CO2 levels before the introduction of modern stations, scientists must use so-called proxy measurements.
These include studying the bubbles of ancient air trapped in Antarctic ice.
One of these can be used to describe CO2 levels over the past 800,000 years. It suggests that CO2 held steady over this longer period at between 200 ppm and 300 ppm.
A spectacular night-time view of Earth, called Black Marble, has been assembled from a series of cloud-free images acquired by one of the most capable satellites in the sky today – the Suomi spacecraft.
The platform was launched by the US last year, principally to deliver critical meteorological data.
The Black Marble dataset shows off one of Suomi’s key innovations: the low-light sensitivity of its VIIRS instrument.
VIIRS (Visible Infrared Imaging Radiometer Suite) can discern a range of phenomena of interest to weather forecasters – cloud, snow, fog, etc – even when the satellite is on the dark side of the Earth.
Most of the time, all VIIRS needs to do its work is some illumination from the Moon. But if that is not available, the instrument can still detect features down below just from the nocturnal glow of the atmosphere itself.
And, of course, just as this Black Marble rendition demonstrates, VIIRS is also very good at capturing the lights of our cities.
The new imagery was unveiled here at the American Geophysical Union (AGU) Fall Meeting, the largest annual gathering of Earth scientists.
Data from Suomi – a joint NASA and National Oceanic and Atmospheric Administration (NOAA) satellite – is certain to become a mainstay of future presentations at this conference.
Night-time view of Earth, called Black Marble, assembled from a series of cloud-free images acquired by Suomi satellite
VIIRS’ trick is its special day-night band. Unlike a camera that captures a whole picture in one exposure, the day-night band produces an image by repeatedly scanning a scene and resolving it as millions of individual pixels.
The system then reviews the amount of light in each pixel. If it is very bright, a low-gain mode prevents the pixel from oversaturating; if the pixel is very dark, the signal is amplified.
US Air Force satellites have pushed the development of low-light sensors for decades but NASA/NOAA representatives at the AGU meeting said VIIRS had taken the capability to a new level.
One of the instrument’s most important observations of late was to watch Hurricane Sandy as it made landfall over the US in October.
Suomi was launched as the NPP (National Polar-orbiting Operational Environmental Satellite System Preparatory Project) satellite.
It was subsequently renamed in honor of the pioneering Earth observation scientist Verner E. Suomi. The two-tonne, $1.5 billion spacecraft circles the globe, pole to pole, at an altitude just over 800 km.
Its five instruments are tasked with monitoring a huge range of land, ocean, and atmospheric phenomena – from the temperature and humidity of the air, to the spread of algal blooms in the ocean; and from the amount of sunlight bouncing off clouds to the extent of Arctic ice.
US weather specialists warn that a strong solar storm is expected to hit Earth shortly and it could disrupt power grids, satellite navigation and plane routes.
The solar storm – the largest in five years – will unleash a torrent of charged particles between 06:00 GMT and 10:00 GMT, specialists say.
The experts say it was triggered by a pair of massive solar flares earlier this week.
It means there is a good chance of seeing the northern lights at lower latitudes, if the skies are clear.
The effects will be most intense in polar regions, and aircraft may be advised to change their routings to avoid these areas.
“It’s hitting us right in the nose,” said Joseph Kunches, an expert at the US National Oceanic and Atmospheric Administration (NOAA).
US weather specialists warn that a strong solar storm is expected to hit Earth shortly and it could disrupt power grids, satellite navigation and plane routes
Joseph Kunches described the storm as the Sun’s version of Super Tuesday – in a reference to the US Republican primaries and caucuses in 10 states.
“Space weather has gotten very interesting over the past 24 hours,” Joseph Kunches added.
The charged particles are expected to hit Earth at 4,000,000 mph (6,400,000 km/h), and NOAA predicts the storm will last until Friday morning.
Images of the Sun’s region where the flares happened show a complex network of sunspots indicating a large amount of stored magnetic energy.
Other solar magnetic storms have been observed in recent decades.
One huge solar flare in 1972 cut off long-distance telephone communication in the US state of Illinois.
Specialists announce that the sun is today bombarding Earth with radiation from the biggest solar storm in almost seven years, with more to come from the fast-moving eruption.
The solar storm occurred at about 11: 00 p.m. Eastern Time on Sunday and will hit Earth with three different effects at three different times.
The biggest issue is radiation, which is mostly a concern for satellite disruptions and astronauts in space. It can cause communication problems for polar-travelling aeroplanes, experts said.
Radiation from Sunday’s flare arrived at Earth an hour later and will probably continue through until Wednesday, experts say. Levels are considered strong but other storms have been more severe.
There are two higher levels of radiation on the National Oceanic and Atmospheric Administration’s storm scale of “severe” and “extreme”, space weather centre physicist Doug Biesecker said.
This storm is the strongest for radiation since May 2005. The radiation – in the form of protons – came flying out of the sun at 93 million miles per hour.
“The whole volume of space between here and Jupiter is just filled with protons and you just don’t get rid of them like that,” Doug Biesecker said, explaining why the effects will stick around for a couple of days.
Radiation from Sunday's flare arrived at Earth an hour later and will probably continue through until Wednesday
NASA’s flight surgeons and solar experts examined the solar flare’s expected effects.
They decided that the six astronauts on the International Space Station do not have to do anything to protect themselves from the radiation, spokesman Rob Navias said.
A solar eruption is followed by a one-two-three punch, said Antti Pulkkinen, a physicist at NASA’s Goddard Space Flight Center in Maryland and Catholic University.
First comes electromagnetic radiation, followed by radiation in the form of protons. Then, finally the coronal mass ejection – that’s the plasma from the sun itself – hits.
Usually that travels at about 1 or 2 million miles per hour, but this storm is particularly speedy and is shooting out at 4 million miles per hour, Doug Biesecker said.
Plasma causes much of the noticeable problems on Earth, such as electrical grid outages. In 1989, a solar storm caused a massive blackout in Quebec. It can also pull the northern lights further south.
But this coronal mass ejection seems likely to be only moderate, with a chance for becoming strong, Doug Biesecker said. The worst of the storm is likely to go north of Earth.
And unlike last October, when a freak solar storm caused auroras to be seen as far south as Alabama, the northern lights aren’t likely to dip too far south this time, Doug Biesecker said.
Parts of New England, upstate New York, northern Michigan, Montana and the Pacific Northwest could see an aurora but not until Tuesday evening, he said.
For the past several years the sun had been quiet. Part of that was the normal calm part of the sun’s 11-year cycle of activity.
Last year, scientists started to speculate that the sun was going into an unusually quiet cycle that seems to happen maybe once a century or so.
Now that super-quiet cycle doesn’t seem as likely, Doug Biesecker said. Scientists watching the sun with a new NASA satellite launched in 2010 – during the sun’s quiet period – are excited.
“We haven’t had anything like this for a number of years,” Antti Pulkkinen said. “It’s kind of special.”
Particles from a recent solar storm will slam today into Earth and produce amazing Northern Lights, or auroras. On the downside, experts expect radio blackouts for a few days, caused by the radiation from the flare – or coronal mass ejection (CME) – causing magnetic storms.
The flare is part of a larger increase in activity in the Sun, which runs in 11-year cycles. It is expected to peak around 2013.
The National Oceanic and Atmospheric Administration’s Space Weather Prediction Center wrote: “Category G1 (Minor) geomagnetic storms are expected 28 and 29 December due to multiple coronal mass ejection arrivals. R1 (Minor) radio blackouts are expected until 31 December.”
A coronal mass ejection (CME) contains billions of tons of gases bursting with X-rays and ultraviolet radiation that are flung into space at around 5 million mph.
They are mind-bogglingly hot – around 100,000,000 C.
The Earth is occasionally hosed by these ejections, leading to amazing shimmering light shows.
They are caused by the ionized solar particles becoming imprisoned by Earth’s magnetic field, exciting the gases in the atmosphere and emitting bursts of energy in the form of light.
A coronal mass ejection (CME) contains billions of tons of gases bursting with X-rays and ultraviolet radiation that are flung into space at around 5 million mph
However, these particles can also cause magnetic storms, which in extreme cases have been known to disrupt satellites and electricity grids.
In 1989, a CME was held responsible for leaving six million people in Quebec, Canada, without power.
Last month one of the largest storms our star can produce was detected.
Known as an X1.9 flare, it was one of the biggest seen in years.
The flare was so powerful that it disrupted communications systems on earth around 45 minutes later.
Another gigantic flare occurred in August, but because it took place on the side of the Sun not facing Earth, there was no disruption to communications or power.