Atlantic Quiet For Now

The area of disturbed weather that brought heavy rain to southeastern Texas and parts of Louisiana on Wednesday is now well inland. Moisture from this system will feed more showers and thunderstorms today through the southern Plains.

Elsewhere across the tropical Atlantic we are tracking tropical waves along 35 west, south of 15 north, along 46 west, south of 22 north, along 67 west, south of 24 north and along 84 west, south of 20 north. All waves with the exception of the wave along 64 west are moving west at about 6-7 degrees longitude per day.

The wave along 67 west is moving west at 8-10 degrees longitude per day as it starts to interact with the Atlantic high to the north. This high is producing a stronger pressure gradient over the Greater Antilles. This wave will bring the eastern and northeastern Caribbean a few showers and thunderstorms, but it is moving too fast to bring any prolonged rainfall. A large mass of African Dust showing up on both the United States and European satellite images of the Atlantic is causing any showers and thunderstorms with this wave to diminish quickly. This wave will bring showers into the southern Bahamas and Hispaniola tomorrow and tomorrow night, then might enhance shower and thunderstorm development over the northern Bahamas and perhaps into southeastern Florida, Friday night into Saturday morning.

Disturbed weather in the western Gulf of Mexico might become an organized tropical system

An area of disturbed weather in the western Gulf of Mexico is being watched for possible development within the next 24 to 36 hours. We are carefully monitoring a couple of low pressure areas along or just off the coast of Mexico just east and northeast of Tampico crawling northward toward the south Texas coast. This area of low pressure could be evolving into a tropical depression. As long as the low pressure areas stay near the coast frictional forces will slow and perhaps inhibit development. An upper level low over northeast Mexico is creating southwest upper level winds over the system. This is creating some shear over the feature and this is another inhibiting factor for development. We believe the shear being caused by the upper level low will decrease over the next 24 hours. If the shear diminishes enough and the surface low pressure moves a bit more off the coast then this feature could wrap up into an organized tropical system very quickly. Since the system is disorganized all the stronger winds and persistent heavy rainfall is well to the east and northeast, well offshore. In a system like this the heavier rainfall will remain north and east of the weak low pressure center. If the thunderstorms and rain start to wrap around the surface low pressure area that will be a sign of organization. We did not see that happen during Monday afternoon. Reguardless of whether this becomes better organized the system will bring heavy rainfall to parts of coastal Texas during the next 36 hours. We expect the surface low pressure area to track northward which will bring that feature just east of Brownsville by Tuesday morning then due east of Corpus Christi by late Tuesday afternoon. The surface low pressure area will move into east Texas during Wednesday. So, if it's going to organize and devleop it will have to do so by Wednesday morning.

Calm in the Atlantic, For Now

There is only one area of concern in the Atlantic basin. Thunderstorms are clustered in the Bay of Campeche in the wake of a tropical wave that has moved into Mexico. Currently, upper-level westerly winds are strong, shearing the thunderstorms apart and preventing further development. However, should the thunderstorms persist for another 24 hours, the upper-level winds should eventually relax and become more favorable for development as a ridge builds over the region. Whether or not development occurs, some of this moisture will be pulled northward into southern Texas tonight and Tuesday, resulting in heavy thunderstorms in those areas.
Another tropical wave is moving through the eastern Caribbean and is located along 79 west south of 20 north, moving west-northwest at 15 knots. There is very little thunderstorm activity along this wave.

Another couple of waves are progressing westward through the Atlantic. One wave is located along 67 west south of 18 north, moving west at 15 knots. There is little thunderstorm activity along this wave as well because of very dry air aloft over the region. The other wave has moved east of the Cape Verde Islands and is along 43 west south of 20 north. This wave has a well-defined low pressure area in association with it, but Saharan dust has become entrained with the system, choking off the thunderstorms that were along the wave earlier. So, development cannot occur along this wave anytime soon.

Tropical Storm Beryl hits Massachusetts

Tropical Storm Beryl quietly made landfall on Nantucket early Friday, bringing a steady, driving rain to coastal Massachusetts. Hours later, it moved out to sea, leaving little but a soaking in its path.

The storm's center hit around 3 a.m., said Jack Beven, hurricane specialist with the National Hurricane Center in Miami.

The wind and rain started to pick up just after midnight, said Rocky Fox, owner of the Chicken Box bar there. But he wasn't scared: "It's the kind that puddles quick," he said. "To us it's just a big old Nor'easter."

Officials said the region fared well. The Coast Guard said they hadn't heard of problems, and no power outages were reported.

"It looks like a gray, rainy day," said Nantucket Fire Department Capt. Steve Murphy as he looked out the window.

A tropical storm warning issued from the coast of Massachusetts was discontinued Friday morning, according to the National Hurricane Center in Miami. Areas affected included Cape Cod, Nantucket and Martha's Vineyard.

At 5 a.m. EDT, the storm had maximum sustained winds of about 50 mph, and was about 35 miles northeast of Nantucket. It was expected to weaken over the next 24 hours and lose tropical characteristics by Saturday morning.

It was moving at about 21 mph and was expected to increase in speed Friday, forecasters said. The center of Beryl was expected to be near or over Nova Scotia late Friday or early Saturday.

The Coast Guard was monitoring about 50 commercial fishing vessels still on the New England waters near the storm's path late Thursday night, but had no reports of vessels in trouble, said Chief Petty Officer Scott Carr.A tropical storm watch had been issued for eastern Long Island and parts of Connecticut, but was discontinued early Friday as the storm moved northeast.

A tropical storm watch had been issued for eastern Long Island and parts of Connecticut, but was discontinued early Friday as the storm moved northeast.

Workers at Nantucket Moorings on Thursday were making sure their customers' boats were tied down securely, but they weren't panicking.

"That's all we can do for now — make sure lines are secure and people know that the storm is approaching," said Leigh Van Hoven, office manager of the company, which rents and sells moorings.

A record 28 named storms and 15 hurricanes, including destructive Katrina, occurred during last year's June-November Atlantic hurricane season.
The first named storm of the 2006 season, Tropical Storm Alberto, swept over Florida in mid-June, then plowed northward along the coast past the Outer Banks. It was blamed for one drowning.

Beryl Moving Northward Just off Delmarvia Coastline Thursday

A tropical storm warning has been issued for southeastern Massachusetts from Plymouth, southward and westward to Woods Hole. This includes Cape Cod, Nantucket Island and Martha's Vineyard. Additional watches and warnings may be necessary for parts of Long Island and the New England coastline.

Tropical Storm Beryl is about 295 miles south of Nantucket, Massachusetts, packing winds of 60 mph with gusts to 70 mph. As of 5:00 a.m. EDT Thursday, the center of Beryl was located near 37.8 north and 73.2 west. The storm is moving generally to the north at 9 mph. The surface pressure remains at 1002 millibars, or 29.59 inches. Beryl will continue on a northerly track and will increase in forward speed over the next 24 hours. The shear should increase Thursday morning as an upper-level trough approaches from the west, and will help to prevent any significant intensification Thursday. Also, Beryl will be moving over some cooler waters as it continues to head to the north. It should remain a very strong tropical storm through Thursday afternoon as it moves faster and on more of a northeasterly course. The increased shear will then cause the storm to weaken late Thursday and Thursday night. Our forecast will bring the center of Beryl over or near Nantucket early Friday morning. The system should track to the northeast of southeastern New England by later Friday morning and will start to transition to a non-tropical system as it approaches southern Nova Scotia Friday afternoon. Strong winds should continue to stay offshore until the storm moves close to eastern Long Island and over extreme southeastern New England later Thursday night and early Friday morning. We are expecting 15-30 mph winds with gusts to 40 mph along far eastern Long Island and extreme coastal New England. Places like Block Island and Nantucket Island could have higher wind gusts.

The greatest threat with Beryl will be rough surf and rip currents. All the way from Cape Cod southward to Cape Lookout, there will be an increased threat of rip currents. Swimmers and surfers are urged to use extreme caution or even avoid entering the surf through Friday, as rip currents can drown even the best swimmers.

Tropical Storm Beryl Moving North Offshore North Carolina

Tropical Storm Beryl is located 110 miles east-southeast of Cape Hatteras, North Carolina. Beryl continues on a northerly track at 7 mph and maintain tropical storm strength over the next 24 to 48 hours. The storm will track northward, grazing the Outer Banks of North Carolina today. Based on this track, eastern North Carolina and perhaps southeastern Virginia and the Delmarva Peninsula would see some rain squalls with gusty winds tonight, and early Thursday before the storm accelerates northeastward with similar conditions around Cape Cod on Friday.

A tropical storm watch remains in effect for the North Carolina coast from north of Cape Lookout to south of Currituck Beach Light.

Residents of the Outer Banks of North Carolina should be completed with storm preparations at this point, as this area will at least be brushed by Beryl. Those along the coast all the way to Cape Cod should keep a close watch on Beryl's progress, as any deviation west of the forecast track would result in areas around the coast to be directly affected. Outside of the main danger area, Beryl will cause rip currents, rough surf and some beach erosion, as well as possible coastal flooding along the Carolina and mid-Atlantic coasts.

Elsewhere in the Atlantic, there are a few tropical waves to follow. One tropical wave is moving across the Yucatan Peninsula and will eventually move over the Bay of Campeche Wednesday. The close proximity to land should prevent further organization or strengthening

Another tropical wave is along 68 west, south of 25 north. It is causing thunderstorms over the eastern Caribbean.

A third tropical wave in the open Atlantic, near 35 west, south of 16 north. There could be development along this wave over time as well, since the waters are progressively warmer in the path of the wave and there is no significant shear in the region.

Fast Flood Facts from FloodSmart.gov

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• Floods and flash floods happen in all 50 states.
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• Just an inch of water can cause costly damage to your property.
• Flash floods often bring walls of water 10 to 20 feet high.
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• Hurricanes, winter storms and snow melt are common (but often overlooked) causes of flooding.
• New land development can increase flood risk, especially if the construction changes natural runoff paths.
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It takes 30 days after purchase for a policy to take effect, so it's important to buy insurance before the floodwaters start to rise.
• All claims and expenses of the NFIP program are funded by insurance premiums, not tax dollars.

Making Waves

The next tropical wave to be concerned with is roughly along 70 west, south of 20 north. It is moving west-northwestward at about 15 knots. There are no signs of organization with this wave at the moment and shear caused by westerly winds aloft will prevent any development along this wave in the near future. The wave is causing showers and thunderstorms in Puerto Rico and the Virgin Islands Thursday night that will reach Hispaniola Friday. This wave will eventually reach South Florida by Sunday.

A weak wave is around 54 west, south of 12 north. There are a few scattered showers from this system, but no development is expected.

Another tropical wave is out over the open Atlantic to the southwest of the Cape Verde Islands along 30 west, south of 15 north. There appears to be an area of low pressure along this wave centered near 27 west and 13 north, as evidenced by a swirl of clouds on satellite pictures of the region. While in minimal shear at this point it will continue to head toward a region where more shear is expected. Development is not expected.

Another wave is moving through western Africa and should form another Atlantic tropical wave later Friday.

A Tropical Wave East of the Lesser Antilles Might Have Favorable Conditions for Development in a Few Days

We are tracking tropical waves along 74 west and along 53 west. The wave along 74 west extends to about 21 north and is moving to the west at 10-15 knots or about 6 degrees longitude per day. This wave is causing an increase in clouds, showers and thunderstorms over the Bahamas and eastern Cuba, as well as parts of Columbia. That wave will help bring a moisture surge into South and central Florida Wednesday and Thursday. A large area of dry air follows this wave over the Leeward Islands.

The wave along 53 west has a curved cloud structure that extends up to about 15 north with a 1012 mb low associated with it. This wave is moving westward at about 6 degrees longitude per day. Microwave satellite images show clusters of thunderstorms and a slight rotary motion in the thunderstorm pattern. This is often the beginning sign of a possible low-level or upper-level feature forming. For the first time this tropical season, the shear has relaxed over the Lesser Antilles and the eastern Caribbean. Current shear in the path of this wave is generally less than 10 knots and that is not enough to kill the wave. Another problem with this season thus far has been higher-than-normal surface pressures over the Caribbean. Current surface data indicates that surface pressures are lower today compared to last week and are near normal for the most part. If surface pressure continues to lower and the shear continues to relax over the eastern Caribbean and near the Lesser Antilles, this wave could try to organize in a few days. This wave will move into the Lesser Antilles Wednesday night and Thursday.

Model forecast tracks / A normal July

Model forecast tracks for the tropical wave approaching the Lesser Antilles Islands.

The curve of historical normal hurricane activity of the Atlantic Ocean.

Tropical Development Unlikely

A tropical wave is causing a few showers and thunderstorms from Puerto Rico to just north of the Dominican Republic and northward still into the Bahamas. While there is considerable convection with this wave, there will be little organized storminess at this point. These thunderstorms have been ongoing for the past 24 hours, but tropical development is unlikely over the coming days due to wind shear and stronger-than-average surface pressures in their path. This disturbance should reach Florida by Wednesday, causing an increase in thunderstorm activity.

Another tropical wave is located near 44/45 west, south of 15 north and is moving to the west at 15 knots. Thunderstorms have become better organized with the wave, and a small surface low with a minimum pressure of 1012 mb has developed. This wave shows small promise for future development, but it will also be entering an area of some wind shear near the Leeward Islands.

Disturbed weather in the northwest Caribbean is being watched

An upper level system, extending from near Florida toward the southwest across the southeast Gulf of Mexico and into the northwest Caribbean Sea, continues to generate showers and thunderstorms from the U.S. southeast coast southwest into the northwest Caribbean. A surface low will devleop along a weak front moving into the southeast U.S. and become better developed near the Carolina coast later today and Saturday then lift northeast. We see no tropical development with this low. However, a tropical wave along 85 west near 22 north angles back south southwest into the northwest Caribbean. This tropical wave is interacting with the upper level system and this is leading to enhanced thunderstorms from western Cuba southward into eastern Nicarague and Honduras. Surface pressures in this area remain too high for possible development within the next couple of days and the wave is moving westward at about 7 to 8 degrees longitude per day. So, this feature will be over the Yucatan tomorrow, slow down and move into the southwest Gulf Saturday night and Sunday. There is a slight chance this system could organize in the far southwest Gulf of Mexico on Sunday.

Elsewhere in the Atlantic Basin a tropical waves along 60 west and along 45 west are moving west at about 15kts. Both waves are surrounded by African dust at this time. This dust will continue to suppress thunderstorm development in and around these tropical waves. A new wave is emerging off the African coast just east of 20 west. t too is surrounded by dust and the thunderstorms around it will probably diminish witin the next 24 hours as it heads west.

A large area of African dust covers the eastern Caribbean eastward across the tropical Atlantic. As we have been stating all week this large area of dust is creating a strong inversion which will continue to suppress convective development. Given no large scale shower and thunderstorm development it will be very difficult for any tropical development over the eastern Caribbean into the western tropical Atlantic for the next few days.

Tropical Atlantic remains quiet

The Atlantic Basin continues to look fairly quiet. We continue to monitor an area of clouds, showers and thunderstorms over the northern Bahamas into southeast Florida. This area of disturbed weather is associated with a weak upper level low that is centered near Miami Florida. This upper level feature will move west northwest over the next 24 hours then become oval shaped and oriented northeast to southwest on Friday as an upper level system moves into the Southeast U.S.. A weak cool front supported by this upper level system dropping into the Southeast U.S. will reach northern Florida tomorrow night. This very complex weather pattern will cause a surface low to form over southeast Georgia tomorrow night. That low pressure are will move northeast close to the South and North Carolina coast during Friday and Friday night. This will not be a tropical feature at this point. However, it could become a non tropical storm system as it moves northeast Friday night and Saturday.

Elsewhere in the tropics we are monitoring tropical waves along 76 west south of 22 north, along 52 west south of 11 north and along 35 west south of 13 north. These waves are moving to the west at about 15-20 knots or about 7 degrees longitude per day. The wave along 76 west is enhancing thunderstorm development over eastern Cuba and over the southern Caribbean. But there is little shower or thunderstorm development over the middle Caribbean. We expect this wave to be along 82 west late tomorrow and near 90 west by Friday evening. This will help produce an increase in thunderstorms over the Yucatan peninsula during Friday. This wave might be something to watch over the weekend as it moves into the Bay of Campeche or the southwest Gulf of Mexico.

Florida coral battered by hurricanes and disease

DRY TORTUGAS NATIONAL PARK, Florida (Reuters) - In the azure waters of Florida's remote Dry Tortugas National Park, corals have been toppled by hurricanes and blighted by disease and a phenomenon known as bleaching.

Eight hurricanes in two years and a plague of disease that swept the Caribbean recently have damaged the colorful, thick carpets of open-water coral reefs in the 100-square-mile (260-sq-km) park off Florida's southwest coast.

With another hurricane season under way and diseases such as white plague getting an early start this year, scientists surveying the reef expressed heightened concern for the fragile corals, which are important nurseries and habitats for marine life and harbingers of the health of the seas.

"There are some areas out here that are like a parking lot, absolutely denuded," said Dr. Jerry Ault, associate professor of marine biology and fisheries at the University of Miami's Rosenstiel School of Marine & Atmospheric Science.

Ault supervised a team of nearly 40 divers aboard the 100-foot (30-meter) research vessel Spree recently as they conducted a three-week, $300,000 biennial census, surveying coral, fish and lobster.

The Dry Tortugas are a cluster of seven tiny islands and acres (hectares) of coral seabed located 70 miles southwest of Key West, a popular tourist island at the southern tip of the Florida peninsula.

"Since 2004, we have had eight storms that have tracked within 100 miles of the Tortugas," said Ault. "In 2005, this was ground zero for major storms.

"Are we afraid of another hurricane season? Three (bad) hurricane seasons can't be a good thing."

"Coral reefs are in a state of decline around the world," said Billy Causey, acting regional manager for national marine sanctuaries in the southeast United States. "At least we have protections in place. There's probably not a piece of coral reef real estate that is any more protected."

The Tropical Atlantic remains relatively quiet

The upper level low just east of Florida and a tropical wave along 70 west are our main concerns for any possible tropical development. At this point we don either system within the next couple of days due to strong shear and higher than normal surface pressure. The wave along 70 west is handled differently by various computer models. There is some attempt by one model to show some organization of this wave within the next 3 days. However, we don't see that on other model output. A large area of African dust that we have been stating over the past few days continues to advance westward and is now entering the eastern Caribbean. This African dust represents drier than normal air at about 10,000 feet. This tends to put a lid on thunderstorm development. This drier air is feeding into the back of the wave along 70 west and this will also hinder development.

We are tracking other tropical waves. They are along: 30 west south of 15 north, along 45 west south of 15 north and along 85 west south of 13 north. These tropical waves are moving west at 15-20 knots or about 7 degrees longitude per day. We see no support for any development by any of these waves.

Looking back a year ago for July 4-5 we had two tropical depressions one became Cindy and the other was Dennis. We have had only one tropical cyclone so far this season and this is much closer to a near normal season. We believe the reason we have not seen any quick development like last year is due to several factors. As stated above we are seeing surface pressures a bit higher than normal over the Caribbean compared to lower than normal last year. We also continue to see strong shearing over the eastern Gulf of Mexico down into the Caribbean due to frequent upper level troughs forming over the eastern U.S.. through the Caribbean. Current trends in longer range computer output suggests these conditions should persist through the next 5-7 days and perhaps longer.

Tropical Wave Impacting the Bay of Campeche

A tropical wave along 98 west and south of 20 north is flaring up showers and thunderstorms across the Bay of Campeche. This feature is looking better organized, according to the latest satellite loop, with a large, somewhat concentrated, area of deep convection. However, westerly winds aloft are too strong to allow for fast development or falling pressure. The wave is tracking to the west-northwest at 10-15 knots and will bring beneficial showers and thunderstorms to South Texas over the weekend. If this feature persists for a couple of days and becomes a depression, it could cause flooding rains over eastern Mexico.

A potent tropical wave continues to affect the eastern Caribbean. It is located along 72 west and south of 20 north and is moving west-northwest at 15-20 knots. The wave is causing numerous showers and thunderstorms from Puerto Rico to the Leeward Islands, with a large area of deep convection north of Hispaniola. This convection is being aided by a broad upper-level trough, which is causing southwesterly shear over the system, actually aiding in thunderstorm development much like upper-level shear over the Plains during spring. However, this shear will not allow for tropical development, even though the upper-level trough will move back to the west over the next couple of days, as will the shear, but the wave should continue to track under the shear, slowing the development. Tropical moisture from this wave should increase the chance of showers and thunderstorms across central and South Florida later in the weekend.

Farther east, another tropical wave is located along 54 west and south of 10 north. It is moving west at 15-20 knots and shows little sign of organization. Our last tropical wave is along 38 west and south of 10 north and shows little sign of development.

Tropical Wave Lashes Lesser Antilles and the Virgin Islands

A robust tropical wave continues to produce squally conditions across the Lesser Antilles Thursday. The wave, along 63 west and south of 20 north, is tracking to the west at 15 knots and will move into the western Caribbean later this weekend. It will bring gusty winds and numerous showers and thunderstorms to Puerto Rico today and then Hispaniola on Friday. An upper-level trough is causing a southwest shear across the eastern Caribbean and over the top of this wave so any development will be slow for the time being. The upper-level trough will back to the west over the next couple of days and so will the shear, but if the wave continues to track under the shear, then development will continue to be slow. Tropical moisture from this wave should increase the chance of showers and thunderstorms across central and South Florida later in the weekend.

Another tropical wave along 96 west and south of 20 north is moving west at 10-15 knots, but convection associated with it has greatly diminished. Moisture from this wave will bring much-needed showers and thunderstorms to South Texas over the weekend.

Farther east, another tropical wave is located along 47 west and south of 10 north. It is moving west at 10-15 knots and shows little sign of organization.

Tropical Downpours Continue in East

Low pressure continues to surge northward into the Northeast Wednesday morning, producing tropical downpours from eastern New York into New England. Gales are possible just to the east of the center as well as it moves from western Connecticut toward northern New England. But, the main story will be the flooding rain that will continue over areas that have already been hard-hit over the last couple of months.

Elsewhere in the tropics, a tropical wave is moving through Central America and the Yucatan Peninsula, and is spreading thunderstorms over much of Central America, and the northern end of the wave will cross the Bay of Campeche. There are no signs of organization with the wave at this point, but it is possible that some of this wave's moisture will be pulled into South Texas by Friday, which would result in welcome rainfall in this drought-stricken region. The weather is generally quiet over the rest of the Caribbean at this time. The only other tropical wave to watch is approaching the Lesser Antilles and will cause thunderstorms there Wednesday. This feature also shows no signs of imminent organization.

An upper-level disturbance about halfway between Puerto Rico and Bermuda will continue to move toward the northwest over the next 24 hours. This may begin to affect Bermuda with showers late Wednesday, then pass closer to the island Wednesday night or Thursday.

New threat area east of the Windward Islands

A new area worth watching has cropped up near 7N 47W, about 1050 miles east-southeast of the southern Windward Islands. There is some heavy thunderstorm activity here and a 1012 mb low pressure area has developed. This low is moving west towards an area of higher wind shear, and is not expected to develop. Wind shear over most of the Atlantic is expected to remain seasonably high over the next week, making it difficult for tropical storm formation.

Preliminary model tracks for the low east of the Windward Islands.

Intense storms blamed on heat

Storms blamed on global warming

Global warming, not natural fluctuations in ocean temperature, was the main cause of the ocean heat that energized last year's killer hurricanes, scientists at a federally funded climate laboratory said Thursday.

As a result, continued increases in the Earth's temperature likely will lead to more "enhanced hurricane activity" in future years, said climate analysts Kevin Trenberth and Dennis Shea of the National Center for Atmospheric Research in Boulder, Colo.

Hurricanes draw their energy from the ocean, and scientists on both sides of the debate agree that rising Atlantic Ocean temperatures have driven the past decade's increasingly violent hurricanes.

Last year, for example, the temperature in the tropical Atlantic, where many hurricanes originate, was about 1.6 degrees Fahrenheit above the average for the first 70 years of the 20th century.

The year produced the most named storms on record (28), forcing the National Hurricane Center to go into the Greek alphabet for names. It also brought the most intense Atlantic storm on record (Wilma), the most intense storm to hit the Gulf of Mexico (Rita) and the most destructive storm on record (Katrina).

Some experts, including National Hurricane Center Director Max Mayfield and Colorado State University forecaster William Gray, have discounted the effects of global warming.

They contend that higher ocean temperatures are a result of a long-term cycle known as the Atlantic multidecadal oscillation.

A rise and fall in the ocean's temperature has been documented as far back as the late 1800s.

But in a study described in the Geophysical Research Letters, Trenberth and Shea said the current rise is only partly caused by the oscillation.

They deducted a global temperature increase that scientists have monitored since the 1970s from changes observed in the Atlantic during the same period, and concluded that very little of the increased Atlantic temperature was caused by the ocean temperature cycle.

They attributed 0.8 degrees of the extra temperature to global warming and about 0.2 degrees to the oscillation. The remainder is due to the after-effects of the 2004-05 El Niño warm-water current in the Pacific Ocean and year-to-year variability, they said.

"I don't see how the hell they can say that," said Gray, 76, professor emeritus of atmospheric sciences at Colorado State. "We're just in one of these warming trends due to the ocean circulation and there's nothing we can do about it."

But Georgia Tech scientist Peter Webster, who this year reported that rising ocean temperatures worldwide are directly linked to a 35-year trend of increased hurricane strength, said the calculations by Trenberth and Shea were "fundamentally sound."

"The Atlantic oscillation is there, but it's being out-ridden by global warming," he said.

In a separate report released Thursday, a committee of the National Academy of Sciences said that "proxy" climate records, such as the width of tree rings and the chemical makeup of ice from deep beneath the Greenland snowpack, indicate with "high confidence" that the Earth is warmer now than it has been in the past 400 years.

The academy's study was made at the request of Congress. Industry representatives and global-warming skeptics attacked a earlier proxy temperature study that concluded that the Earth's temperature varied little for 1,000 years, then in the past 25 years began to rise sharply, at an angle reminiscent of a hockey stick.

The study has played a key role in actions by the U.N. Intergovernmental Panel on Climate Change.

The academy panel's study said the proxy evidence provides "less confidence" in climate conditions between 900 and 1600 A.D.

It said "very little confidence" could be placed in average global temperature calculations before 900.