Redoubt volcano unlikely to have a major climate impact
Alaska's Redoubt Volcano continues to erupt, with the latest blast coming just after midnight Eastern time (7:41pm AKDT). The latest eruption threw ash 50,000 feet into the air, but the ash has settled to the ground and the ashfall advisory for cities to the north and northwest of Anchorage such as Talkeetna has expired. Redoubt is located about 100 miles southwest of Alaska's most populous city, Anchorage. The prevailing southerly winds deposited a swath of ash about 200 miles long to the north of the volcano (Figure 1). Redoubt last erupted between December 1989 - April 1990, and its ash clouds presented a major hazard to aviation. On December 16, 1989, Redoubt's eruption spewed ash into the air to a height of 14,000 m (45,000 ft) catching KLM Royal Dutch Airlines flight 867, a Boeing 747 aircraft, in the plume. All four engines stalled and the aircraft plummeted 13,000 feet before the pilot was able to restart the engines and land safely in Anchorage. The total costs to the aviation industry from the 1989 - 1990 eruption were about $100 million. Eighty percent of these costs were due to damaged equipment. For more information on the Redoubt eruption, check out the Alaska Volcano Observatory home page.
Figure 1. Ash on the snow to the north of Alaska's Mt. Redoubt crater in this true color image from NASA's Terra satellite. Image taken 21:49 GMT March 23, 2009. Image credit: Johnathan Dehn, Geographic Information Network of Alaska..
Redoubt's effect on the climate should be minimal
Many historic volcanic eruptions have had a major cooling impact on Earth's climate. However, Redoubt is very unlikely to be one of them. To see why this is, let's examine recent volcanic eruptions that have had a significant cooling effect on the climate. In the past 200 years, Mt. Pinatubo in the Philippines (June 1991), El Chichon (Mexico, 1982), Mt. Agung (Indonesia, 1963), Santa Maria (Guatemala, 1902) Krakatoa (Indonesia, 1883), and Tambora (1815) all created noticeable cooling. As one can see from a plot of the solar radiation reaching Mauna Loa in Hawaii (Figure 2), the Mt. Pinatubo and El Chichon eruptions caused a greater than 10% drop in sunlight reaching the surface. The eruption of Tambora in 1815 had an even greater impact, triggering the famed Year Without a Summer in 1816. Killing frosts and snow storms in May and June 1816 in Eastern Canada and New England caused widespread crop failures, and lake and river ice were observed as far south as Pennsylvania in July and August. Volcanic eruptions cause this kind of climate cooling by throwing large amounts of sulfur dioxide gas into the stratosphere. This gas reacts with water to form sulphuric acid droplets (aerosol particles), which are highly reflective, and reduce the amount of incoming sunlight.
Figure 2. Reduced solar radiation due to volcanic aerosols as measured at Mauna Loa Observatory, Hawaii. Image credit: NOAA/ESRL.
You'll notice from the list of eruptions above that all of these climate-cooling events were from volcanoes in the tropics. Above the tropics, the stratosphere's circulation features rising air, which pulls the sulfur-containing volcanic aerosols high into the stratosphere. Upper-level winds in the stratosphere tend to flow from the Equator to the poles, so sulfur aerosols from equatorial eruptions get spread out over both hemispheres. These aerosol particles take a year or two to settle back down to earth, since there is no rain in the stratosphere to help remove them. However, if a major volcanic eruption occurs in the mid-latitudes or polar regions, the circulation of the stratosphere in those regions generally features pole-ward-flowing, sinking air, and the volcanic aerosol particles are not able to penetrate high in the stratosphere or get spread out around the entire globe. Redoubt is located near 59° north latitude, far from the tropics, and thus is unlikely to be able to inject significant amounts of sulfur aerosols into the stratosphere. Furthermore, the previous 1989 - 1990 eruption of Redoubt (Figure 3) put only about 1/100 of the amount of sulfur into the air that the 1991 eruption of Mt. Pinatubo did, according to the TOMS Volcanic Emissions Group. We can expect the current eruption of Redoubt to be similar in sulfur emissions to the 1989 - 1990 eruption, and have an insignificant impact on global climate.
Figure 3. Amount of sulfur gases put into the air by recent volcanic eruptions. Note that the 1989 eruption of Redoubt put only 1/100 the amount of sulfur dioxide (SO2) into the air that the 1991 eruption of Mt. Pinatubo did. Image credit: TOMS Volcanic Emissions Group.
For more information
Realclimate.org has a nice article that goes into the volcano-climate connection in greater detail. One interesting quote from the article: There can be some exceptions to the tropics-only rule, and at least one high latitude volcano appears to have had significant climate effects; Laki (Iceland, 1783-1784). The crucial factor was that the eruption was almost continuous for over 8 months which lead to significantly elevated sulphate concentrations for that whole time over much of the Atlantic and European regions, even though stratospheric concentrations were likely not particularly exceptional.
scienceblog.com has an interesting article about the largest volcanic eruption of the 20th century--the 1912 eruption of Alaska's Mt. Novarupta, located in the same chain of volcanoes as Mt. Redoubt. According to a NASA computer model, Novarupta's climate-cooling aerosols stayed north of 30°N latitude, and did not cause global cooling. However, the model indicates that the eruption may have indirectly weakened India's summer monsoon, producing an abnormally warm and dry summer over northern India.
Jeff Masters
Reader Comments
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SATURDAY THROUGH SUNDAY...THE ECMWF AND GFS REMAIN IN GOOD AGREEMENT AND SHOW A STRONG SHORTWAVE/UPPER LOW LIFTING NE TOWARD THE GREAT
LAKES OUT OF THE SRN PLAINS. THE GFS PV ANOMALY IS RATHER IMPRESSIVE WITH THIS FEATURE AND EXTENDS DOWN TO 600-700 MB. THIS UPPER FEATURE WILL LEAD TO CYCLOGENESIS AT THE SURFACE OVER THE PLAINS THROUGH THE
DAY FRIDAY. THE TWO MODELS BOTH INDICATE THE LOW DEEPENING TO AROUND 980-990 MB COME SATURDAY WITH A STRONG COLD FRONT EXTENDING SOUTH OVER THE LOWER MS VALLEY. THE FRONT WILL APPROACH THE LOCAL FORECAST AREA FROM THE WEST SATURDAY...THEN THROUGH OUR FORECAST AREA FROM
WEST TO EAST LATE SATURDAY NIGHT INTO SUNDAY. ONE THING THAT STANDS OUT WITH THIS SYSTEM IS THAT BOTH THE KINEMATICS AND THE INSTABILITY
ARE LINING UP FAIRLY WELL. ALTHOUGH WE ARE STILL IN THAT 3-5 DAY WINDOW AND THERE REMAINS SOME UNCERTAINTY...THIS WILL NEED TO BE
MONITORED OVER THE NEXT FEW DAYS.
Stay safe all and we shall see what happens as the weekend approaches...........WW
I think I'm safe from the bad weather here in SE FL :)
Redoubt remains at Aviation Color Code RED and Alert Level WARNING. Seismic activity at the volcano is currently relatively low, and no activity is observed in partly cloudy web camera images. Pilot reports and satellite images indicate that a steam plume is currently rising to at least 20,000 ft asl and drifting at least 40 miles to the northwest. We have no indication that the volcano is currently emitting ash, though explosive activity could resume with little or no warning.
The last explosive event occurred last night (March 23) at 7:41 pm (AKDT) and lasted for roughly seventeen minutes. The top of the ash cloud was estimated to have reached at least 50,000 ft above sea level based on National Weather Service radar. Winds in the vicinity of the volcano carried the ash cloud primarily to the west and north. Pyroclastic flows were visible traveling down the volcano's north flank in web camera images. Last night's explosive event was the sixth thus far since explosive activity began Sunday, March 22 at 10:38 PM AKDT.
Yesterday, AVO staff visited the area around Redoubt by helicopter to assess conditions and repair equipment damaged by Sunday night's eruptions. They fixed the telemetry link at AVO's observation hut, which is once again transmitting images from the web camera and data from a GPS and two seismic instruments. Clouds obscured the summit, but observers reported very large lahar and flood deposits in the Drift River Valley that likely occurred during and/or following the first five explosions. These flows, which contained ice, water, mud, and other debris, inundated the Drift River Valley and traveled more than 35 km, reaching Cook Inlet. In the middle to upper Drift River Valley, high-water marks reached 6-8 meters above the valley floor. At the AVO hut (roughly 7 miles NNW of the summit), a 6-cm thick fall deposit was observed.
A gas-measurement flight is currently en route to the volcano.
NATIONAL WEATHER SERVICE MELBOURNE FL
200 PM EDT TUE MAR 24 2009
.DISCUSSION...
...ABOVE NORMAL RIP CURRENT RISK THIS WEEK...
...GUSTY SE WINDS ACROSS THE ATLANTIC WATERS THROUGH FRIDAY...
TONIGHT/WEDNESDAY...UPPER LEVEL RIDGE CONTINUES TO BUILD OVER THE
AREA INTO TOMORROW AS HIGH PRESSURE REMAINS NORTH OF THE AREA ALONG
THE EAST COAST. SKIES SHOULD BECOME MOSTLY CLEAR OVERNIGHT WITH
EASTERLY WINDS DECREASING TO AROUND 5-10 MPH. ONSHORE WINDS LOOK TO
BE STRONGEST ALONG THE COAST SOUTH OF THE CAPE WHICH WILL KEEP TEMPS
ELEVATED WITH LOWS IN THE LOW/MID 60S. FARTHER NORTH AND INLAND LOWS
WILL BE IN THE MID/UPPER 50S.
WINDS WILL BECOME MORE SOUTHEASTERLY TOMORROW BUT WILL CONTINUE TO
BECOME BREEZY ALONG THE COAST UP TO 15 TO 20 MPH AND AROUND 15 MPH
INLAND. SLIGHT INCREASE IN MOISTURE WILL OCCUR OVER THE COASTAL
WATERS WHICH MAY ALLOW A FEW SHOWERS TO DEVELOP OFFSHORE...THEREFORE
WENT AHEAD AND ADDED A SLIGHT CHANCE FOR SHOWERS OVER THE MARINE
WATERS WEDNESDAY. HIGHS WILL ONCE AGAIN REACH" onClick="return popup(this, 'notes')">REACH THE MID 70S ALONG THE
COAST TO UPPER 70S/NEAR 80 INLAND.
THU-FRI...A SHORTWAVE WELL NORTH OF THE AREA WILL MOVE NE ACROSS THE
OHIO AND TN VALLEYS AND DRAG A FRONT ACROSS S GA/AL. FRONTAL
CLOUDINESS AND PSBL STORMS WILL REMAIN WELL NORTH OF THE PENINSULA
AS HIGH PRESSURE EAST OF THE STATE KEEPS BREEZY SE/SSE FLOW NEAR THE
COAST. SE FLOW WILL VEER TO SOUTHERLY ON FRIDAY OVER THE INTERIOR
AND SE ALONG THE COAST IN THE AFTERNOON WITH ANOTHER BREEZY
AFTERNOON SEA BRZ. MOISTURE VALUES LOOK TO REMAIN TOO LOW FOR ANY
PRECIP WITH HIGHS IN THE UPR 70S/LWR 80S THU WARMING TO THE LWR-MID
80S ON FRI...A BIT COOLER NEAR THE EAST COAST. THE RISK OF RIP CURRENTS
WILL REMAIN ELEVATED INTO THE UPCOMING WEEKEND WITH ANOTHER SET OF
NE SWELLS AFFECTING THE BEACHES THROUGH LATE WEEK.
SAT-TUE...PREVIOUS DISCUSSION...STRONG H50 SHORT WAVE TROUGH/LOW
MOVG NEWD OUT OF THE CTRL CONUS WILL GRADUALLY BEAT DOWN THE
RIDGE...WITH THE UPR FLOW BECMG GNRLLY ZONAL BY SUN NGT/MON. STRONG
SFC LOW MOVG IN TANDEM WITH THE UPR FEATURE WILL PUSH A COLD FRONT
INTO NORTH FL BY SAT NGT...WHICH WILL SLOW AS IT MOVES GRADUALLY
SEWD THROUGH CTRL FL SUN AFTN/EARLY EVENING. SAT LOOKS TO BE
DOWNRIGHT "HOT" WITH MAXES AT OR NEAR 90F UNDER GUSTY SSW-SW
FLOW...WITH A LATE DAY SEA BREEZE PSBL NR THE SPACE/TREASURE COASTS
THOUGH LKLY PINNED PRETTY CLOSE TO THE BEACH. EARLY SPRING DAYS CAN
SOMETIMES BE NOTORIOUSLY WARMER THAN WHAT EARLY GUIDANCE
SUGGESTS...SO WILL KEEP TABS ON TEMP TRENDS. HAVE NUDGED POPS UP A
BIT FOR BOTH SAT NGT (30/20...MAINLY LATE) AS WELL AS SUN (30 ALL
AREAS) AS FRONT LOOKS TO HAVE A DECENT MOISTURE BAND ASCD WITH
IT...AS WELL AS SOME MID/UPR LVL SUPPORT. HAVE HELD OFF ON MENTION
OF TS...GIVEN THE UNCERTAINTY IN DIURNAL TIMING. SLGTLY COOLER/DRIER
FOR MON. WITH FRONT STALLING ACROSS SOUTH FL...THERE COULD BE A BIT
MORE IN THE WAY OF CLOUDS NR LAKE OKEE MON.
MADE SOME MINOR ADJUSTMENTS TO FCST EARLY NEXT WEEK AND FOLLOWED
06Z/12Z GFS AND 00Z ECM WHICH DRIES AIRMASS OUT BEHIND THE FRONT.
WILL KEEP NEW DAY7 DRY AT THIS POINT WITH SFC HIGH BUILDING NEAR THE
AREA AND PWATS DROPPING BELOW A HALF INCH.
WOW! Redoubt is hangin' more ash than Groucho Marx or George Burns.
Nice Post Skyepony
Don't forget Boss Limbaugh!
Groucho and Snopes or no Snopes? "I love my cigar, but I take it out now and then."
Yes, but...
(there is always a but, isn't there?)
if enough ash were deposited far enough north, I expect we see an faster than normal (an eventually more extensive) ice melt later in the spring in the Arctic. Of course this will be determined as 'proof' of global warming even if the temps do not support it and consideration that the signal may be contaminated will not happen.
AP: Oil terminal a concern as Alaska volcano rumbles
1 hour ago
ANCHORAGE, Alaska (AP) — An Alaska volcano continued to rumble Tuesday amid new concerns that eruptions and mud flows will damage a nearby oil terminal where about 6 million gallons of crude are stored. The 10,200-foot Mount Redoubt volcano, about 100 miles southwest of Anchorage, erupted Sunday night. Since then there have been five more explosions; the latest, on Monday night, shot an ash plume into the air that was 40,000 to 50,000 feet high.
So far !!!
Still some activitiy on the Ring of Fire.
Magnitude Location Time
6.0 New Britain region, Papua New Guinea 2 hours ago Map
4.8 Tonga 7 hours ago Map
5.2 Northern Mid-Atlantic Ridge 13 hours ago Map
Unlike weather, sometimes the fuse is ingnited far,far away. Lets see if this volcano has more to say. ↨
Volcano in Alaska may have screwed up computer models
I should add that is the same general area that exhibited activity about 48 hours prior to the eruption associated with Redoubt.. Keep an eye on this the next few days, or sooner. This occured at 30 miles in depth. That typically will produce other events. That is deeper than the others in that area recently.
Tropical Cyclone Advisory Number FOUR
TROPICAL CYCLONE JASPER (CAT 1)
12:00 PM FST March 25, 2009
==================================
At 0:00 AM UTC, Tropical Cyclone Jasper, Category One [987 hPa] is located at 21.2S 162.9E has 10 minute sustained winds of 45 knots close to the center decreasing to 35 knots in the next 6-12 hours. The cyclone is reported as moving west-northwest at 3 knots. Position FAIR based on multispectral infrared/visible imagery with animation.
Gale Force Winds
==============
60 NM of the center in northern semi-circle
200 NM of the center in the southern semi-circle
Low level circulation center is exposed more than 1 degree to north of deep convection. Effects of shear and dry air entrainment evident. Outflow remains good to south but poor elsewhere. Jasper is currently being steered westwards by a low level ridge to the south.
Dvorak analysis based on shear yielding DT=2.0, MET=2.0, PT=2.0. FT based on MET
Thus T2.0/3.0/W1.5/24HRS.
The system is currently under a 20 knot shear. Global models agree on a westerly track and weakening.
Forecast and Intensity
=======================
12 HRS: 21.3S 162.2E - 35 knots (CAT 1)
24 HRS: 21.4S 162.0E - 30 knots (TROPICAL DEPRESSION)
48 HRS: 21.4S 160.4E - 20 knots (T.D.)
Hey Vortex....your not blog killing are ya....LOL
The true windy days of Spring!
That would be Drift River... there are some awesome images on the AVO website from their fly-overs yesterday.
Sulfur aerosols tend to cool by blocking sunlight which may cancel the effect & how dark is the ash compared to the black soot from burning resources that we know is warming the arctic 5º? After looking at pictures of both I'm not convinced soot is lighter than ash. It's worth looking at numbers.
Tropical Cyclone Warning Number FIVE
TEMPETE TROPICAL MODEREE IZILDA
10:00 AM Réunion March 25 2009
================================
At 6:00 AM UTC, Moderate Tropical Storm Izilda [991 hPa] located at 23.0S 42.1E has 10 minute sustained winds of 40 knots with gusts of 55 knots. The storm is reported as moving south-southeast at 5 knots.
Dvorak Intensity: T3.0
Gale Force Winds
===============
30 NM radius of the center
Near Gale Force Winds
===================
80 NM radius of the center, extending up to 110 NM in the northern semi-circle and up to 160 NM in the southwestern quadrant
Forecast and Intensity
=======================
12 HRS: 23.6S 41.9E - 45 knots (Tempéte Tropicale Moderée)
24 HRS: 23.7S 41.9E - 50 knots (Forte Tempéte Tropicale)
48 HRS: 23.2S 41.3E - 60 knots (Forte Tempéte Tropicale)
72 HRS: 23.1S 40.0E - 40 knots (Tempéte Tropicale Moderée)
Additional Information
=====================
Izilda's convective activity has concentrated within the last 12 hours and has temporarily shows a low defined satellite pattern but improving again within the recent hours. Low level pattern remains however well defined (SSMIS-F17 0222z) and maximum winds of 40 knots are confirmed by last Quikscat swath (0334z). System keeps on tracking slowly south-southeastwards under the steering influence of the mid level ridge existing in its northeast then becoming stationary within the next 24-36 hours due to two opposite steering flows in relationship with the rebuilding mid-level ridge in the southwest. This subtropical ridge is expected to become the main steering flow beyond 36 hours, system is also expected to recurve west-northwestwards. Upper level jet (well showed on infrared METEOSAT-7 imagery) existing in the west and in the south of the system is expected to keep on improving the upper level poleward divergence but could become a limiting factor as the system recurves west-northwestwards (Beyond 36 hrs) linked to strengthening wind shear.
extending into Saturday for nearly the same southern U.S. states.
A CATEGORICAL SLIGHT RISK WILL BE INTRODUCED ATTM DUE TO THE
ABOVE-MENTIONED UNCERTAINTIES. HOWEVER...SHOULD MODEL GUIDANCE
REMAIN CONSISTENT WITH THE CURRENTLY FORECAST
THERMODYNAMIC/KINEMATIC PARAMETERS...AN UPGRADE TO AT LEAST MODERATE
RISK WILL BE REQUIRED IN SUBSEQUENT OUTLOOKS.
Furthermore, where I live is under a 30% chance of severe weather this far out, which is quite rare to see -- I get the feeling this area will eventually be upgraded to a High Risk.
Gale Force Winds
=================
150 NM of the center in the southern semi-circle
The low level circulation center is exposed and effects of shear and dry air entrainment evident. Jasper is currently being steered westward by a low level ridge to the south.
Dvorak analysis based on shear yielding DT=MET=PT=1.5 FT based on MET.
Thus T1.5/3.0/W2.0/24HRS
The system is currently under 20 knot shear. In the short term, global models agree on a southwesterly movement before recurving the system on a northwesterly track and weakening it further.
Forecast and Intensity
=======================
12 HRS: 21.5S 163.0E - 30 knots (TROPICAL DEPRESSION)
24 HRS: 21.3S 162.1E - 25 knots (T.D.)
FINAL TROPICAL DISTURBANCE ADVISORY ON THIS SYSTEM UNLESS REGENERATION OCCURS..
Sky you are Correct. Sulfur dioxide partiticles tend to reflect sunlight causing cooling not heating. Atmo i'm not sure how you see warming occuring. Just my opinion but, i just don't see warming.
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