Too *much* Ice blocks Iceland fish supply

[Flubber]

Oh and for Mobius

http://en.wikipedia.org/wiki/Iceberg

http://en.wikipedia.org/wiki/Pack_ice

Read these and you may start to understand why you don't see a polar bear typically on an iceberg

[chequita guevara]

Originally posted by Oerdin
More likely it is all that cold fresh water coming off of the melting glaciers in Greenland which is to blame. Or at least that would be my guess.

My guess would be that the glaciers are moving into the fjords faster because of melting.

[Flubber]

Just as long as you guys understand that this ice pack is frozen sea ice and not parts of glaciers themselves.

[chequita guevara]

Okay, so this is Greenlandish ice.

[Flubber]

Originally posted by chegitz guevara
Okay, so this is Greenlandish ice.

WEll it makes a difference. More icebergs is from warmer temperatures causing more glacial melt. Pack ice moving south is usually a result of COLD temperatures and wind/wave conditions that do not break up the pack.

One can argue that warming leading to glacial melt can later result in the cooling that results in the pack ice or that the change in wind \wave conditions is a result of warming but those connections are much more tenuous

[Lul Thyme]

I didn't follow the whole conversation, but it is true that is very misleading to try and link every weather event with global warming.

Global warming is about very large scale climate, and the predictions it makes about local climate are vague, and even within that there is still room for huge amounts of variation (seasonal etc..)

[MOBIUS]

Originally posted by Flubber
Now you were being intentionally obtuse.

You said:

Don't be silly. Increased calving is a possible explanation but so is a winter with increased pack ice and onshore winds-- Both could have polar bears as both could and would come down from up north

I rest my case.

[MOBIUS]

Originally posted by Flubber
Your analysis simplistic.

Evidently not simplistic enough for you...

Claiming this Iceland event is an effect of global warming without evidence is superficial.

The IS evidence, as already mentioned! If you decide to close your mind to it and stick your head in the sand, it doesn't mean it goes away!

The fact that it happened 40 years ago shows that warming is NOT a necessary precondition.

Agreed. However we have come up with plausible reasons why it might be happening now. Whereas all you've brought to the table is 'something' like this happened before... Big deal, but it doesn't make this not global warming.

Could this be caused by climate change ? Sure it could.. . . All I am sick of is people jumping on EACH and EVERY weather event as conclusive proof of something. Taken together and analyzed correctly they may prove lots of things. But taken individually with no analysis its just crap

And I am sick of all the blinkered tw@ts who stick their fingers in their ears shouting "I'm not listening, I'm not listening!", so I guess we're even...

Several events are occurring in the region that could very plausibly point to global warming causing the pack ice blocking the fisheries of NW Iceland. Cause and effect. Besides, I'm sure someone is analysing this as we speak - but it'll take a while and until then I as a non-Climatologist do not have any access to the data as I alluded to in my 1st post...

[MOBIUS]

Originally posted by Flubber
Oh and for Mobius

http://en.wikipedia.org/wiki/Iceberg

http://en.wikipedia.org/wiki/Pack_ice

Read these and you may start to understand why you don't see a polar bear typically on an iceberg

Whilst I admit I may have incorrectly attributed the ice to Icebergs initially, it still doesn't change the fact that the freshwater melt essentially floats on the surface, thus potentially deflecting the pack ice away from Greenland, and towards Iceland. Not to mention the weakened Gulf Stream, making it easier for the ice to flow against (again towards Iceland). Also, with the Arctic being warmer anyway, this might have the effect of affecting prevailing wind conditions and their relative strengths to create this sort of event...

Sounds logical to me.

[MOBIUS]

Originally posted by Lul Thyme
I didn't follow the whole conversation, but it is true that is very misleading to try and link every weather event with global warming.

Global warming is about very large scale climate, and the predictions it makes about local climate are vague, and even within that there is still room for huge amounts of variation (seasonal etc..)

You can't get more large scale than what is happening to the Gulf Stream, the Greenland ice sheet - the Arctic as a whole!

It is at the poles that the tangible (i.e. NO ONE can deny them) effects of Global Warming are most making themselves felt.

[Dinner]

Originally posted by Flubber
Just as long as you guys understand that this ice pack is frozen sea ice and not parts of glaciers themselves.

That is well understood. Now, if you have increased amounts of freshwater which is at or maybe one degree above freezing and you put massive quantities of it into the ocean is it concievable that it could alter the local ocean temperature? I say, yes, it is concievable. I'm not certain if that is exactly what is happening though I recall hearing that 3 to 4 times greater an area of Greenland is ice free in the summer then used to be. That's a lot of melting ice. Additionally if you get enough calving ice then even if it melts before getting to Iceland all that ice also might depress temperatures of the water.

The major problem with this theory of course is that this is still late winter so theoritically the melt shouldn't have started yet. I do know that the poles heat up a lot more then other parts of the globe due to climate change though as the ice used to reflect heat back into space but the water (which used to be covered with ice) absorbs heat.

[Flubber]

Originally posted by MOBIUS




The IS evidence, as already mentioned! If you decide to close your mind to it and stick your head in the sand, it doesn't mean it goes away!

Ok we have a rare event with pack ice in the area. But what eveidence do you have that this is because of global warming. I accept it is a possible cause but you admit there are other possible causes too . Where is the EVIDENCE that was "already mentioned"?

[Flubber]

Guys get my position straight--


Consider the hurricanes in the US. Two years ago the high level of hurricanes was cited as a result of global warming. Then the following year it seems that hurricane activity was way down.

Was the increased hurricane activity a result of global warming? Maybe. But that alone was not proof of anything just as a relatively hurricane free season is not "proof" that we don't have an issue. If hurrican activity trends upward over a period, we then might have prrof of something


I do not stick fingers in my ears and ignore the issue. BUt I am sick of people on EITHER side of the issue grabbing on to ANY single weather event as if it proves something. The iceland event could be a result of global warming . . . I said that in one of my early posts.

If the average temp in North America this summer is 1 degree warmer or colder than average, it proves nothing. Use real science where you evaluate trends. The trends are what are important and can be alrming in and of themselves. Focussing on specific weather events that have also occurred in the past ( and before any analysis is done) is quite simply counter-productive.

I am interested in why this event has occurred in Iceland. But shouting out the cause today in the absence of any facts is simply ridiculous

[Flubber]

Originally posted by Oerdin


That is well understood. Now, if you have increased amounts of freshwater which is at or maybe one degree above freezing and you put massive quantities of it into the ocean is it concievable that it could alter the local ocean temperature? I say, yes, it is concievable. I'm not certain if that is exactly what is happening though I recall hearing that 3 to 4 times greater an area of Greenland is ice free in the summer then used to be. That's a lot of melting ice. Additionally if you get enough calving ice then even if it melts before getting to Iceland all that ice also might depress temperatures of the water.

The major problem with this theory of course is that this is still late winter so theoritically the melt shouldn't have started yet. I do know that the poles heat up a lot more then other parts of the globe due to climate change though as the ice used to reflect heat back into space but the water (which used to be covered with ice) absorbs heat.

The other problem is that it seems like North Atlantic ocean temperatures are generally increasing. THis article is from 2005 but makes the point. The waters off newfoundland would be affected by glacial melt similar to Iceland

Ocean temperatures in the North Atlantic hit an all-time high last year, raising concerns about the effects of global warming on one of the most sensitive and productive ecosystems in the world.

Sea ice off the coast of Newfoundland and Labrador was below normal for the tenth consecutive year and the water temperature outside St. John's Harbor was the highest on record in 2004, according to a report released Wednesday by the federal Fisheries Department.

The ocean surface off St. John's averaged one degree Celsius above normal, the highest in the 59 years the department has been compiling records.

And bottom temperatures were also one degree higher than normal, according the report.

"A one-degree temperature anomaly on the Grand Banks is pretty significant in the bottom areas, where temperatures only range a couple of degrees throughout the year," said Eugene Colbourne, an oceanographer with the Fisheries Department.

Water temperatures were above normal right across the North Atlantic last year, from Newfoundland to Greenland, Iceland and Norway.

The Newfoundland data is another wake-up call on climate change, say environmentalists.

Anchorage, Alaska, has seen annual snowfall shrink in the past decade, high river temperatures are killing off millions of spawning salmon in British Columbia and northern climates around the world have noticed warming.

Meanwhile, ocean temperatures have risen around the globe, and species are already dying, said Bill Wareham, acting director of marine conservation for the Vancouver-based David Suzuki Foundation.

"I don't think there's a question about whether these changes are happening," Wareham said.

But "everyone's quite shocked at the speed at which these things are changing."

Air temperatures in the Newfoundland region were also higher than normal, but Colbourne said the results are not conclusive.

Water temperatures in the cold Labrador current were actually below normal levels. And while the other temperatures were record highs, a similar warming trend occurred in the 1960s, Colbourne said.

"We really can't say for sure if what we're seeing in Newfoundland waters is a consequence of global warming, when we've only got 50 years of data or so," Colbourne said.

"It may be related to global warming but, then again, it may be just the natural cycle that we see in this area of the world."

Still, climate change is high on the agenda this week at the G8 meeting in Scotland, where British Prime Minister Tony Blair hopes to persuade the world's wealthiest nations to sign a deal on climate change despite bitter opposition from the United States.

Going into the meetings, U.S. President George Bush ruled out any Kyoto-type deal but did say that global warming is an issue that needs to be dealt with.

In an interview with a British television station, Bush conceded, for the first time, that human activity was "to some extent" to blame.

THIS type of year over year analysis is much more significant than attributing causes to a single anomolous event. I find this information very worrying. BUt at the same time, the fact that we only have 59 years of data means that we are unsure as to causation

[Flubber]

Here's the scientific stuff -- See here http://journal.nafo.int/34/colbourne/4-colbourne.html for the complete paper

Basically what it says is that the Ocean off of Newfoundland warmed through the 50s and 60s and then began cooling in the 70s such that some of the coolest temperatures on record occurred in 1991. Then a rapid warming began to some of the warmest temperatures on record by the late 90s

I haven't completely absorbed this but it seems that higher northen melt rates are equating to WARMER not colder temperatures at sea. According to the report, the times of highest sea temps to the south corresponded to the years with the greatest melting

Discussion and Summary

The latter half of the 20th century has been a period of considerable variability in the physical environment in NAFO waters of the Northwest Atlantic. During the decades of the 1950s and 1960s the ocean environment was dominated by a general warming phase that reached its maximum by the mid-to-late 1960s. Beginning in the early-1970s however, climate conditions in the Northwest Atlantic experienced near-decadal oscillations, with a general downward trend in ocean temperatures. The decadal mean temperatures show that the 1950s and particularly the 1960s were the warmest in the 50-plus year record and the decade of the 1990s was the third consecutive decade with below normal temperatures on the Newfoundland Shelf. The magnitude of the negative salinity anomaly on the inner Newfoundland Shelf during the decade of the 1990s was comparable to that experienced during the 'Great Salinity Anomaly' of the early-1970s.

In summary, during the last several decades, water properties (temperature/salinity) on the Newfoundland Shelf showed extreme variability, often exhibiting different phase responses during different time periods both within and between decades. During the 1990s, for example, the Northwest Atlantic experienced some of the most extreme variations in ocean conditions since measurements began in the mid-1940s. Off eastern Newfoundland and on the southern Labrador Shelf bottom temperatures ranged from near record lows during 1991 to some of the highest values on record by the late 1990s. The extreme variability in water properties is due to differences in the phase and amplitude in the seasonal cycles of solar heat input, air-sea sensible and latent heat fluxes, sea ice dynamics and variations in advection rates of the Labrador Current. The sea-surface pressure field, from which the NAO index is derived and which is one of the largest scale forcing mechanisms affecting the ocean climate in the North Atlantic, also experienced extreme spatial variability during the end of the 1990s. This resulted in a breakdown in the expected ocean response in the Northwest Atlantic to changes in the NAO patterns, particularly during 1999 and 2000 (ICES, 2001; Colbourne and Anderson, 2003).

One common feature in the ocean climate during the past three decades however, is the extremely cold-water temperature during the early part of each decade and the generally warmer conditions towards the second half of each decade. This was especially true during the decade of the 1990s. For example, the three highest CIL areas measured on the Newfoundland Shelf occurred during 1972, 1984 and 1991 along all three sections shown in Fig. 1. On the other hand, there was a significant difference in the water salinity on the inner Newfoundland Shelf between the decade of the 1990s and the previous two decades. Salinities during the 1990s at most depths remained below normal throughout the decade, in contrast to the previous two decades when salinities increased more or less in phase with the increasing temperature trends during the latter half of each decade. The source of the freshwater observed at Station 27 during the early 1990s was assumed to be due to increased amounts of fresh water from melting sea-ice off Labrador. However, the source of the increased amounts of freshwater during the latter part of the 1990s needs to be investigated. The record high air temperatures experienced in northern regions during the late 1990s may have led to increased amounts of sea ice melting at higher latitudes (Parkinson et al., 1999), resulting in larger amounts of freshwater flowing south throughout most of the year.

The NAFO waters of the Northwest Atlantic and particularly the Newfoundland and Labrador shelf regions are a habitat to many marine species of demersal fish and crustacean populations. Many of these species are at the northern limit of their distributions within a very limited thermal habitat. It is not unreasonable therefore, to expect changes in ocean temperature at this northern limit to be an important factor influencing marine production. Indeed, several studies have suggested that variations in the physical ocean environment influences growth, recruitment and distribution of many marine organisms in Newfoundland waters (deYoung and Rose, 1993; Myers et al., 1993; Rose et al., 1994; Rose et al., 1995; Taggart et al., 1994; Narayanan et al., 1994; Colbourne et al., 1997b; Carscadden et al., 2001; Parsons and Lear, 2001; Colbourne and Anderson, 2003). The interactions between the marine environment and production, however, are complicated, usually non-linear, and operate through complex mechanisms throughout several trophic levels of the ecosystem over a broad range of time and space scales. These interactions are further complicated by variations in fishing mortality. Therefore, the significance of correlations between individual environmental indices and measures of marine production is most often marginal at best and often breaks down as different factors predominate.

The analysis presented here suggests that the ocean climate on the Newfoundland Shelf has changed on decadal time scales with the last three decades all showing significantly lower average temperatures compared with the 1950s and 1960s. Coincident with these climate variations many commercial fish species have shown dramatic changes in distribution and abundance on similar time scales. Recruitment in Newfoundland cod stocks, for example, declined almost steadily since the 1960s, reaching historical low values by the early-1990s (Stansbury et al., MS 1999; Lilly et al., MS 1999). The correlations shown in Fig. 12 between the air temperatures, the area of CIL water, and Atlantic cod (Gadus morhua) recruitment with the NAO are consistent with the scenario outlined by Mann and Drinkwater (1994) on the physical mechanisms that lead to ecosystem productivity. We find strong correlations between the NAO and air temperatures and the amount of CIL water on the Newfoundland Shelf. Furthermore, high recruitment in the southern Grand Bank cod (Div. 3NO) is associated with negative NAO anomalies and generally warmer ocean climate conditions.

Within the decade of the 1990s water properties in the Newfoundland region have experienced extreme variations from record low ocean temperatures during the first half of the decade to a record high by the late 1990s. This shift in the thermal habitat from the Arctic-like conditions of the early-1990s to the more temperate conditions of the late-1990s most likely contributed to the observed changes in the pelagic ecosystem, which showed a significant increase in the nekton biomass during the late-1990s (Anderson et al., MS 1999; Dalley et al., MS 2000; Colbourne and Anderson, 2003). In addition, data from the annual multi-species bottom trawl surveys of NAFO Divisions 2J3KLNO (Fig. 1) while showing only a slight increase in the biomass of cod from 1995 to 1997 showed a 70% increase from 1998 to 1999 during the fall survey (DFO, 2000). Finally, the recently observed expansion in the spatial distribution and increase in abundance of yellowtail flounder (Limanda ferruginea) on the Grand Bank coincided with the improved thermal environment during the latter half of the 1990s (Walsh et al., MS 2000; Colbourne and Bowering, MS 2001). In conclusion, the progressive decline in ocean temperatures, particularly during the past two decades, coincided with the general decline in fish production in Newfoundland waters. However, as noted above, fish production in general depends on many other complex physical and biological processes in addition to changing fishing mortality