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Sea Surface Temperatures Reach Record Highs On Northeast Continental Shelf

Vergent

By Vergent,
in Climate Change

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The_Global_Warmer

The_Global_Warmer

Posted
Posted

It was warmer before so I have been told and the AMO is as always a big player.

These are historically warm waters in modern human history going back to 1854 by by 3F and 1.5C over 2nd place 1951.

Friedland said the average sea surface temperature (SST) exceeded 10.5 degrees C (51°F) during the first half of 2012, exceeding the previous record high in 1951. Average SST has typically been lower than 9 degrees C (48°F) over the past three decades. Sea surface temperature in the region is based on both contemporary satellite remote-sensing data and long-term ship-board measurements, with historical SST conditions based on ship-board measurements dating back to 1854.

In some nearshore locations like Delaware and Chesapeake Bays in the Middle Atlantic Bight region, temperatures were more than 6 degrees C (11°F) above historical average at the surface and more than 5 degrees C (9°F) above average at the bottom. In deeper offshore waters to the north, bottom waters were 1 degree C (2°F) warmer in the eastern Gulf of Maine and greater than 2 degrees C (3.6°F) warmer in the western Gulf of Maine.

The ocean bottom temperature data came from a variety of sources, including eMOLT, a cooperative research program between the Northeast Fisheries Science Center and lobstermen who deploy temperature probes attached to lobster traps. While some of the temperature probes from the eMOLT program are still in the water and have not yet been returned, those that have been returned indicate that bottom water temperatures in 2012 were the warmest since the eMOLT program began in 2001.

Atlantic cod distribution in the Gulf of Maine continues a northeasterly shift, with the spring 2012 data consistent with a response to ecosystem warming. Warming ocean temperatures and the resulting impact on the distribution of 36 fish stocks was reported by the Center in a 2009 study published in Marine Ecology Progress Series. That study analyzed annual NEFSC spring survey data from 1968 to 2007 and other information and found that about half of the 36 fish stocks studied in the Northwest Atlantic Ocean, many of them commercially valuable species, have been shifting northward over the past four decades, with some disappearing from US waters as they move farther offshore.

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TerryM

TerryM

Posted
Posted

"What is known is that things are changing, and we need to continue monitoring and adapting to these changes."

Perhaps if the good folks would just legislate that the waters not warm, all these problems would disappear.

Here in Canada, we're much more advanced, we simply stop monitoring anything that might prove distressing to the tar sands industry.

Terry

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ORH_wxman

ORH_wxman

Posted
Posted

It was warmer before so I have been told and the AMO is as always a big player.

These are historically warm waters in modern human history going back to 1854 by by 3F and 1.5C over 2nd place 1951.

Still in denial mode about the AMO?

I thought you would have read up more on it by now.

1.) The fact that the previous record in their analysis is 1951 should speak something

2.) With an underlying warming trend, we would expect records to be broken. This says nothing about whether a major oscillation exists in the SST readings of the Atlantic.

3.) I tried to discuss this with you previously, and you never responded to the post I made when you claimed the AMO wasn't a big factor for SSTs off the Northeast coast of U.S and Nova Scotia....this is the post:

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The_Global_Warmer

The_Global_Warmer

Posted
Posted

"What is known is that things are changing, and we need to continue monitoring and adapting to these changes."

Perhaps if the good folks would just legislate that the waters not warm, all these problems would disappear.

Here in Canada, we're much more advanced, we simply stop monitoring anything that might prove distressing to the tar sands industry.

Terry

here in the United States we blame the AMO.

No one can actually break out a map and show me the last 6 months where water came out of the Atlantic(sub surface). Or apparently use argos data to show us where this layer of perpetual warmth that some how will switch to perpetual cold on 30 month intervals.

On top of that modeled data talks about a 0.2C swing in either positive or negative outside of the pattern influential warming. 0.2C in one direction or another is the difference between a negative 30 yr period and a positive one.

The AMO was negative Dec-Feb. Now it's nearing record highs in the positive direction in 6 months. We both know that is externally driven. I am supposed to hedge my bets on correlation analysis, regression analysis of a presumed sub-surface layer of water that is warm for 30 years then cold for 30 years, not telling me how it actually goes from warm to cold just that is what it does.

Then people take more correlations mind you, not direct forcing, for instance dirty ice on Greenland = record low albedo = record high solar insolation = warm melt water and persistent Dipole Anomaly's that help keep High Pressure system's in place longer over Greenland the NW Atlantic, thus warming the Baffin Bay, water is carried around the Bay to the North where that heat meets up with the heat from the directly observable Pollyanna, that heat goes South as the Labrador Current that is supposed to bring cooler waters to the region of record ssts this year.

That doesn't get mentioned, Obviously if the cool water flowing South is 2, 3, 5C+ to warm it might have more of an impact than the 0.2C swinging AMO that's heat goes with the gulf stream to the Barrent's Sea, not the Eastern Nova Scotia coast.

I read about the AMO. I do not dispute the existence of slight up's and down's in the North Atlantic SSTs for general periods, I think it's way overblown. You will hear how rainfall in florida or something is higher during positive AMO period's. So what? It doesn't mean the unknown origins of the AMO are the direct forcing. Putting quite a bit to much faith a in a 0.2C correlation from sst changes.

What I find most is many modes of action working together that are very unpredictable over a longer term of scale of climate. I would conclude at this time that these movers and shakers represent no more than 08% of seasonal variabilityy and 20% of MDV.

http://www.nature.com/ncomms/journal/v2/n2/full/ncomms1186.html

Understanding the internal ocean variability and its influence on climate is imperative for society. A key aspect concerns the enigmatic Atlantic Multidecadal Oscillation (AMO), a feature defined by a 60- to 90-year variability in North Atlantic sea-surface temperatures. The nature and origin of the AMO is uncertain, and it remains unknown whether it represents a persistent periodic driver in the climate system, or merely a transient feature. Here, we show that distinct, ~55- to 70-year oscillations characterized the North Atlantic ocean-atmosphere variability over the past 8,000 years. We test and reject the hypothesis that this climate oscillation was directly forced by periodic changes in solar activity. We therefore conjecture that a quasi-persistent ~55- to 70-year AMO, linked to internal ocean-atmosphere variability, existed during large parts of the Holocene. Our analyses further suggest that the coupling from the AMO to regional climate conditions was modulated by orbitally induced shifts in large-scale ocean-atmosphere circulation.

ncomms1186-f1_zpsebc2296e.jpg?t=1348024635

Some more info:

http://icesjms.oxfordjournals.org/content/69/5/706.short

The ICES Report on Ocean Climate presents the latest information on the status and trends of sea temperature and salinity in the North Atlantic and Nordic Seas. It is the main product of the ICES Working Group on Oceanic Hydrography, published annually. Bringing together multiple time-series from across the ICES and NAFO regions offers insight into the concurrent spatial and temporal trends in ocean temperature and salinity. This paper presents an overview of the physical variability in the North Atlantic Ocean at decadal and longer time-scales and reviews the current state of understanding of the causes and mechanisms of this variability. Between the 1960s and the 1990s, the North Atlantic Oscillation (NAO) index increased from a persistent negative phase in the 1960s to a strong positive phase during the 1980s and early 1990s. However, during the decade 2000–2009, because of shifts in atmospheric pressure patterns, the NAO was weak and the NAO index was not a good indicator of atmospheric forcing. Marked changes were also observed in oceanographic indices such as the Subpolar Gyre index during the mid-1990s and, as a consequence, conditions in the decade 2000–2009 have been very different from those of the previous four decades.

another possible expanation for this:

http://www.springerlink.com/content/m8n25vv254216632/

In order to understand potential predictability of the ocean and climate at the decadal time scales, it is crucial to improve our understanding of internal variability at this time scale. Here, we describe a 20-year mode of variability found in the North Atlantic in a 1,000-year pre-industrial simulation of the IPSL-CM5A-LR climate model. This mode involves the propagation of near-surface temperature and salinity anomalies along the southern branch of the subpolar gyre, leading to anomalous sea-ice melting in the Nordic Seas, which then forces sea-level pressure anomalies through anomalous surface atmospheric temperatures. The wind stress associated to this atmospheric structure influences the strength of the East Greenland Current across the Denmark Strait, which, in turn, induces near-surface temperature and salinity anomalies of opposite sign at the entrance of the Labrador Sea. This starts the second half of the cycle after approximatively 10 years. The time scale of the cycle is thus essentially set by advection of tracers along the southern branch of the subpolar gyre, and by the time needed for anomalous East Greenland Current to accumulate heat and freshwater anomalies at the entrance of the Labrador Sea. The Atlantic meridional overturning circulation (AMOC) does not play a dominant role in the mode that is confined in the subpolar North Atlantic, but it also has a 20-year preferred timescale. This is due to the influence of the propagating salinity anomalies on the oceanic deep convection. The existence of this preferred timescale has important implications in terms of potential predictability of the North Atlantic climate in the model, although its realism remains questionable and is discussed.

One more:

http://cat.inist.fr/?aModele=afficheN&cpsidt=25697652

The sea surface temperature (SST) variability of the Bay of Biscay and adjacent regions (1854-2010) has been examined in relation to the evolution of the Atlantic Multidecadal Oscillation (AMO), a major climate mode. The AMO index explains ~25% of the interannual variability of the annual SST during the last 150 years, while different indices of the North Atlantic Oscillation (NAO) explain ≤1% of the long-term record. NAO is a high frequency climate mode while AMO can modulate low frequency changes. Sixty per cent of the AMO variability is contained in periods longer than a decade. The basin-scale influence of NAO on SST over specific years (1995 to 1998) is presented and the SST anomalies explained. The period analysed represents an abrupt change in NAO and the North Atlantic circulation state as shown with altimetry and SST data. Additional atmospheric climate data over a shorter ~60 year period (1950-2008) show the influence on the Bay of Biscay SST of the East Atlantic (EA) pattern and the Scandinavia (SCA) pattern. These atmospheric teleconnections explain respectively ~25% and ~20% of the SST variability. The winter SST in the shelf-break/slope or poleward current region is analysed in relation to AMO. The poleward current shows a trend towards increasing SSTs during the last three decades as a result of the combined positive phase of AMO and global warming. The seasonality of this winter warm flow in the Iberian region is related to the autumn/winter seasonality of south-westerly (SW) winds. The SW winds are strengthened along the European shelf-break by the development of low pressure conditions in the region to the north of the Azores and therefore a negative NAO. AMO overall modulates multidecadal changes (~60% of the AMO variance). The long-term time-series of SST and SST anomalies in the Bay of Biscay show AMO-like cycles with maxima near 1870 and 1950 and minima near 1900 and 1980 indicating a period of 60-80 years during the last century and a half. Similar AMO-like variability is found in the Russell cycle of the Western English Channel (1924 - 1972). AMO relates at least to four mesozooplankton components of the Russell cycle: the abundance of the chaetognaths Parasagitta elegans and Parasagitta setosa (AMO-), the amount of the species Calanus helgolandicus (AMO-), the amount of the larvae of decapod crustaceans (AMO-) and the number of pilchard eggs (Sardine pilchardus; AMO+). In addition to AMO, the decadal to multidecadal (D2M) variability in the number of sunspots is analysed for the last 300 years. Several periodicities and a multi-secular linear increase are presented. There are secular minima near 1710, 1810, 1910 and 2010. The long term variability (> 11 years) of the solar sunspot activity explains ~50% of the variance of the SST of the Bay of Biscay with periods longer than 11 years. AMO is finally compared with the Pacific Decadal Oscillation, the leading principal component of North Pacific SST anomalies.

This paper finds extreme fluctiations in the AMO's alleged influence on Greenland over different areas. Which means asumming any event to the AMO seems fool hardy when just over a small ice island there is such extreme variability.

http://www.agu.org/pubs/crossref/2012/2012GL051241.shtml

The Greenland δ18O ice core record is used as a proxy for Greenland surface air temperatures and to interpret Atlantic Multidecadal Oscillation (AMO) variability. An analysis of annual δ18O data from six Arctic ice cores (five from Greenland and one from Canada's Ellesmere Island) suggests a significant AMO spatial and temporal variability within a recent period of 660 years. A dominant AMO periodicity near 20 years is clearly observed in the southern (Dye3 site) and the central (GISP2, Crete and Milcent) regions of Greenland. This 20-year variability is, however, significantly reduced in the northern (Camp Century and Agassiz Ice Cap) region, likely due to a larger distance from the Atlantic Ocean, and a much lower snow accumulation. A longer time scale AMO component of 45–65 years, which has been seen clearly in the 20th century SST data, is detected only in central Greenland ice cores. We find a significant difference between the AMO cycles during the Little Ice Age (LIA) and the Medieval Warm Period (MWP). The LIA was dominated by a ∼20 year AMO cycle with no other decadal or multidecadal scale variability above the noise level. However, during the preceding MWP the 20 year cycle was replaced by a longer scale cycle centered near a period of 43 years with a further 11.5 year periodicity. An analysis of two coupled atmosphere-ocean general circulation models control runs (UK Met Office HadCM3 and NOAA GFDL CM2.1) agree with the shorter and longer time-scales of Atlantic Meridional Overturning Circulation (AMOC) and temperature fluctuations with periodicities close to those observed. However, the geographic variability of these periodicities indicated by ice core data is not captured in model simulations.

Finally a paper talking about mechanism of action!

http://adsabs.harvard.edu/abs/2012EGUGA..1410074R

To better assess the decadal predictability of the climate system, its internal variability is investigated here over the North Atlantic - Europe region at multidecadal timescale using the 1000-yr preindustrial control run (constant external forcings set to 1850) of the CNRM-CM5 model within the 5th Coupled Model Intercomparison Project framework. The model so-called Atlantic Multidecadal Variability/Oscillation (AMV/AMO) estimated from sea surface temperature (SST) anomalies is very close to observations both in terms of pattern and amplitude. A preferred timescale around 100yr dominates the model AMV and is found to be a damped mode of variability. We show that a strengthening of the Atlantic Meridional Overturning Circulation (AMOC) leads by about 5 years the maximum of AMV. Enhanced AMOC is preceded by about 30 years by the so-called East Atlantic Pattern atmospheric circulation (negative anomalous pressure monopole located in the center of the North Atlantic basin) and/or the Scandinavian mode (see-saw between Greenland and Scandinavia). The anomalous atmospheric circulations force a northward oceanic heat transport intensification of the eastern branch of the subpolar gyre and through the Iceland-Faroe strait leading to an increase of heat transport between the subpolar gyre and the Norvegian sea. The concurrent subsurface and SST warming is advected along the Norvegian gyre and precludes sea ice formation along the eastern Greenland Coast leading to positive surface salinity anomalies due to enhanced local evaporation The latter is advected by the mean circulation along Greenland to the Labrador Sea where it drives deeper convection about 20-yr before a maximum of AMOC. By geostrophy, the subpolar gyre intensifies bringing extra heat and salt from its southern edge. The current anomaly gradually propagates backward along the Western boundary current (Gulf Stream etc.) up to the equator. Associated with a northward shift of the tropical Atlantic Inter-Tropical Convergence Zone (ITCZ) and predominant negative North Atlantic Oscillation atmospheric circulation. These all together product an increase of northward heat transport into the Atlantic ocean leading in fine to AMV maximum. This cycle takes about 30-40 years to build and is damped about 20 years later by negative salinity anomalies advected into the subpolar gyre from the western tropical Atlantic basin, due to ITCZ changes.
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TerryM

TerryM

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Posted

Friv

Is there evidence that the Labrador current is heating? I don't mean temps off Maine, but further north, say the east coast of Labrador. If so I think it would prove your contention. No one could reasonably argue that AMO would affect the outflow of Arctic waters through Baffin Bay, and if the Labrador current is heated it's certainly the cause of elevated temps off Maine.

Terry

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dabize

dabize

Posted
Posted

Thats an interesting idea, Terry.

Especially since one might expect the Labrador Current to have an expanded volume and if anything lower SSTs due to the increased degree of melting in the GIS this year - assuming that SI melting in Baffin Bay and the CAA is not a factor (due to YTY stability imposed by geographic constraints).

Not quite sure what to make of this, actually.

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