Archives par mot-clé : Ocean

Undersea earthquakes shake up climate science

by C. Rotter, Sep 20, 2020 in WUWT


Despite climate change being most obvious to people as unseasonably warm winter days or melting glaciers, as much as 95 percent of the extra heat trapped on Earth by greenhouse gases is held in the world’s oceans. For that reason, monitoring the temperature of ocean waters has been a priority for climate scientists, and now Caltech researchers have discovered that seismic rumblings on the seafloor can provide them with another tool for doing that.

In a new paper publishing in Science, the researchers show how they are able to make use of existing seismic monitoring equipment, as well as historic seismic data, to determine how much the temperature of the earth’s oceans has changed and continues changing, even at depths that are normally out of the reach of conventional tools.

They do this by listening for the sounds from the many earthquakes that regularly occur under the ocean, says Jörn Callies, assistant professor of environmental science and engineering at Caltech and study co-author. Callies says these earthquake sounds are powerful and travel long distances through the ocean without significantly weakening, which makes them easy to monitor.

Wenbo Wu, postdoctoral scholar in geophysics and lead author of the paper, explains that when an earthquake happens under the ocean, most of its energy travels through the earth, but a portion of that energy is transmitted into the water as sound. These sound waves propagate outward from the quake’s epicenter just like seismic waves that travel through the ground, but the sound waves move at a much slower speed. As a result, ground waves will arrive at a seismic monitoring station first, followed by the sound waves, which will appear as a secondary signal of the same event. The effect is roughly similar to how you can often see the flash from lightning seconds before you hear its thunder.

 

IMAGE: AN ARTIST’S RENDERING OF UNDERSEA EARTHQUAKE WAVES. view more CREDIT: CALTECH

Acid Oceans? & Oyster Shells

by Jim Steele, July 14, 2020 in WUWT


(I wrote a white paper for the CO2  Coalition, providing more details and references to peer reviewed science regards how marine life counteracts ocean acidification. That paper can be downloaded here )

Search the internet for “acid oceans” and you’ll find millions of articles suggesting the oceans are becoming more corrosive due the burning of fossil fuels, and “acid oceans” are threatening marine life. Although climate modelers constantly claim the oceans’ surface pH has dropped since the 1800s, that change was never measured, as the concept of pH was not created until the early 1900s by beer-makers.

In 2003 Stanford’s Dr. Ken Caldeira coined the term “ocean acidification” to generate public concern about increasing CO2  . As New Yorker journalist Elizabeth Kolbert reported, “Caldeira told me that he had chosen the term ‘ocean acidification’ quite deliberately for its shock value. Seawater is naturally alkaline, with a pH ranging from 7.8 to 8.5—a pH of 7 is neutral—which means that, for now, at least, the oceans are still a long way from actually turning acidic.” Nonetheless Caldeira’s term “ocean acidification” evoked such undue fears and misunderstandings, we are constantly bombarded with catastrophic media hype and misdiagnosed causes of natural change.

For example, for nearly a decade the media has hyped the 2006-2008 die-off of larval oysters in hatcheries along Washington and Oregon. They called it a crisis caused by rising atmospheric CO2  and the only solution was to stop burning fossil fuels. But it was an understanding of natural pH changes that provided the correct solutions. Subsurface waters at a few hundred meters depth naturally contain greater concentrations CO2  and nutrients and a lower pH than surface waters. Changes in the winds and currents periodically bring those waters to the surface in a process called upwelling. Upwelling promotes a burst of life but also lowers the surface water pH.  Not fully aware of all the CO2  dynamics, the hatcheries had made 3 mistakes.

Arctic Ocean changes driven by sub-Arctic seas

by University of Alaska Fairbank, July 12, 2020 in WUWT


New research explores how lower-latitude oceans drive complex changes in the Arctic Ocean, pushing the region into a new reality distinct from the 20th-century norm.

The University of Alaska Fairbanks and Finnish Meteorological Institute led the international effort, which included researchers from six countries. The first of several related papers was published this month in Frontiers in Marine Science.

Climate change is most pronounced in the Arctic. The Arctic Ocean, which covers less than 3% of the Earth’s surface, appears to be quite sensitive to abnormal conditions in lower-latitude oceans.

“With this in mind, the goal of our research was to illustrate the part of Arctic climate change driven by anomalous [different from the norm] influxes of oceanic water from the Atlantic Ocean and the Pacific Ocean, a process which we refer to as borealization,” said lead author Igor Polyakov, an oceanographer at UAF’s International Arctic Research Center and FMI.

Although the Arctic is often viewed as a single system that is impacted by climate change uniformly, the research stressed that the Arctic’s Amerasian Basin (influenced by Pacific waters) and its Eurasian Basin (influenced by Atlantic waters) tend to differ in their responses to climate change.

Since the first temperature and salinity measurements taken in the late 1800s, scientists have known that cold and relatively fresh water, which is lighter than salty water, floats at the surface of the Arctic Ocean. This fresh layer blocks the warmth of the deeper water from melting sea ice.

IMAGE: A MAP OF THE ARCTIC OCEAN SHOWS THE LOCATION OF THE AMERASIAN AND EURASIAN BASINS. ARROWS SHOW THE PATH OF WARM, FRESH PACIFIC WATER AND WARM, SALTY ATLANTIC WATER INTO… view more CREDIT: GRAPHIC ADAPTED FROM POLYAKOV ET AL. 2020, FRONTIERS IN MARINE SCIENCE PAPER.

Extensive hake (fish) skeletal remains in ocean waters too cold for this species to occupy today suggest past ocean temperatures were several degrees warmer.

by Wheeland & Morgan, July 2020 in NoTricksZone


Fish habitats are limited by specific temperature boundaries. In a new study, for example,  Wheeland  and Morgan (2020) found there was a pronounced ocean warming from the 1980s to late 1990s off the coasts of Greenland. This temperature shift changed the distribution of halibut habitat. Since then, however, there has been no net warming in the study region (through 2016).

Podcast: Why the Oceans Really Aren’t “Acidifying” but the Term Is Being Abused by Science and Media

by A. Watts, June 11, 2020 in WUWT


Science and media outlets claim ocean acidification is happening due to increased carbon dioxide in the atmosphere. But objective data show the ocean is far from acidic according to Dr. Caleb Rossiter, executive director of the CO2 Coalition and a statistician who has studied climate change closely.

Host Anthony Watts and Rossiter talk about how a pH of 7 is considered neutral, with anything below 7 considered acidic. Ocean pH averages 8.1, which is alkaline rather than acidic. Although climate models suggest the ocean’s surface pH may have dropped from pH 8.2 to 8.1 since 1750, that change was never actually measured.

The pH drop from 1850 is merely a modeled conjecture. The concept of pH was first introduced by in 1909, and agriculturalists first developed field instruments to measure pH in the 1930s.

Causes of the Rapid Warming of the North Atlantic Ocean in the Mid-1990s

by P. Homewood, April 9, 2020 in NotaLotofpeopleKnowThat


http://ocean.dmi.dk/arctic/icecover_30y.uk.php

Most of us are probably familiar with the pattern of Arctic sea ice decline between 1979 and 2007, followed by a period of relative stability. Most of the decline took place after the mid 1990s.

The decline is nearly always explained away as the result of global warming, but a couple of old studies show this not to be the case.

In 2011, Robson & Sutton found that the sub polar gyre underwent remarkable and rapid warming in the mid 1990s, and that this was linked to changes in the North Atlantic Oscillation:

The Solution To Dissolution

by Willis Eschenbach, January 31, 2020 in WUWT


The British tabloid “The Guardian” has a new scare story about what is wrongly called “ocean acidification”. It opens as follows:


Pacific Ocean’s rising acidity causes Dungeness crabs’ shells to dissolve

Acidity is making shells of crab larvae more vulnerable to predators and limiting effectiveness in supporting muscle growth

 

The Pacific Ocean is becoming so acidic it is starting to dissolve the shells of a key species of crab, according to a new US study.


Sounds like the end of times, right? So let me start with a simple fact. The ocean is NOT acidic. Nor will it ever become acidic, except in a few isolated locations. It is alkaline, also called “basic”. The level of acidity/alkalinity is expressed on the “pH” scale, where neutral is 7.0, alkaline is from 7 to 14, and acidic is from 0 to 7.

Figure 1. The pH scale, running from the most acid at the bottom, through neutral in the middle, and up to the most alkaline at the top.

From the chart, the ocean has a pH of around 8 (although as we’ll see, that conceals great variation).

 

DEEP DIVING SCIENTISTS DISCOVER “SODA SPRINGS” — AN UNDERWATER ENVIRONMENT WHERE HIGH CO2 CONCENTRATIONS (UP TO 95,000 PPM) BUBBLE-UP FROM THE OCEAN FLOOR

by Cap Allon, January 27, 2020 in Electroverse


University of Texas at Austin Professor, Bayani Cardenas, has discovered an underwater environment of bubbling carbon dioxide with readings some 200x the concentration of CO2 in the atmosphere.

Cardenas discovered the region –which he calls “Soda Springs”– while studying how groundwater from a nearby island could affect the ocean environment of the Verde Island Passage in the Philippines. The passage is one of the most diverse marine ecosystems in the world and is home to thriving coral reefs.

The amazing bubbling location, which Cardenas captured on video, is not a climate change nightmare, reads part of the press release issued by utexas.edu on Jan 22, 2020. It is instead linked to a nearby volcano that vents out the gases through cracks in the ocean floor, and has probably been doing so for decades or even millennia.

Continuer la lecture de DEEP DIVING SCIENTISTS DISCOVER “SODA SPRINGS” — AN UNDERWATER ENVIRONMENT WHERE HIGH CO2 CONCENTRATIONS (UP TO 95,000 PPM) BUBBLE-UP FROM THE OCEAN FLOOR

Des réchauffements répétitifs sans CO2 ?

by P. Berth & A. Préat, 24 janvier 2020 in ScienceClimatEnergie


Depuis le début des mesures thermométriques directes, les 4 principales séries de température  que nous possédons (thermomètres terrestres et satellites) nous montrent que la température globale de la basse troposphère a augmenté de ± 0,8°C en 138 ans (entre 1880 et 2018). Cela correspond à ± 0,28°C en 50 ans soit 0,006°C/an(actuellement environ 0,01°C/an pour les 30 dernières années). Les médias nous rappellent chaque jour que cette hausse est exceptionnelle et que le CO2 anthropique en est à l’origine, c’est-à-dire est le grand coupable suivant la terminologie consacrée.

Mais cette vitesse d’augmentation de la température, est-elle vraiment exceptionnelle? Dans les lignes qui suivent, nous allons vous démontrer qu’il n’en est rien. Au cours de la dernière période glaciaire, alors que l’espèce humaine existait déjà, la température moyenne a parfois augmenté à une vitesse vingt fois plus élevée, et ce à de nombreuses reprises. Ces phénomènes particuliers, qui n’ont pas fait disparaître la vie sur Terre, et que nous vous avions déjà mentionnés sur SCE (ici), sont appelés évènements de Dansgaard-Oeschger ou ‘DO’ (des noms des deux scientifiques -danois et suisse-  qui furent les premiers à les mettre en évidence) et sont reconnus par le GIEC. Comme nous allons vous le montrer dans le présent article, le taux de CO2 n’aurait qu’un rôle mineur dans ces évènements.

Figure 1. Stratigraphie isotopique de l’oxygène à partir des glaces du forage GRIP (Groenland).
En ordonnée valeurs du δ
18O en ‰ et en abscisse profondeur en mètres du forage (Cronin, 2010). Les compositions isotopiques de l’oxygène sont un indicateur de la température. La figure montre de manière très claire que l’interglaciaire actuel (Holocène, moitié gauche du graphique) est caractérisé par des fluctuations thermiques de faible amplitude (si l’on excepté un épisode plus froid vers 8,2 ka) alors que le Dernier Glaciaire (moitié droite du graphique) montre des changements climatiques fréquents, rapides et de grandes amplitudes (de 8°C à 16°C suivant les δ18O) enregistrés pas les événements ou ‘cycles’ DO (Dansgaard-Oeschger events). Nb: YD pour Younger Dryas, correspondant à un refroidissement il y a 12800 ans BP (non discuté dans cet article).

 

New 80-Year Deep-Ocean Temperature Dataset Compared to a 1D Climate Model

by Roy Spencer, January 15, 2020 in WUWT/Ch.Rotter


The increasing global ocean heat content (OHC) is often pointed to as the most quantitative way to monitor long-term changes in the global energy balance, which is believed to have been altered by anthropogenic greenhouse gas emissions. The challenge is that long-term temperature changes in the ocean below the top hundred meters or so become exceedingly small and difficult to measure. The newer network of Argo floats since the early 2000s has improved global coverage dramatically.

A new Cheng et al. (2020) paper describing record warm ocean temperatures in 2019 has been discussed by Willis Eschenbach who correctly reminds us that such “record setting” changes in the 0-2000 m ocean heat content (reported in Zettajoules, which is 10^^21 Joules) amount to exceedingly small temperature changes. I calculate from their data that 2019 was only 0.004 0.009 deg. C warmer than 2018.

Over the years I have frequently pointed out that the global energy imbalance (less than 1 W/m2) corresponding to such small rates of warming is much smaller than the accuracy with which we know the natural energy flows (1 part in 300 or so), which means Mother Nature could be responsible for the warming and we wouldn’t even know it.

The Cheng (2017) dataset of 0-2000m ocean heat content changes extends the OHC record back to 1940 (with little global coverage) and now up through 2019. The methodology of that dataset uses optimum interpolation techniques to intelligently extend the geographic coverage of limited data. I’m not going to critique that methodology here, and I agree with those who argue creating data where it does not exist is not the same as having real data. Instead I want to answer the question:

If we take the 1940-2019 global OHC data (as well as observed sea surface temperature data) at face value, and assume all of the warming trend was human-caused, what does it imply regarding equilibrium climate sensitivity (ECS)?

Fig. 1. Deep-ocean temperature variations 1940-2019 explained with a 2-layer energy budget model forced with RCP6 radiative forcing scenario and a model climate sensitivity of 1.85 deg. C. The model also matches the 1940-2019 and 1979-2019 observed sea surface temperature trends to about 0.01 C/decade. If ENSO effects are not included in the model, the ECS is reduced to 1.7 deg. C.

Throwing More Cold Water On An Alarmist Ocean-Warming Paper

by Dr. D. Whitehouse, January 17, 2020 in ClimateChangeDispatch


It’s the usual story. It’s the beginning of the year and the statistics of the previous year are hurriedly collected to tell the story of the ongoing climate crisis.

First off, we have the oceans which, according to some, are living up to the apocalyptic narrative better than the atmosphere.

The atmosphere is complicated, subjected to natural variabilities, that make the temperature increase open to too much interpretation.

The oceans, however, are far more important than the air as they absorb most of the anthropogenic excess heat.

Looking at the literature reveals no one knows just how much excess heat (created in the atmosphere) it mops up or indeed exactly how or where it does it. Some say it is 60% which is a bit on the low side, most say 90% or 93%.

The real figure is unknown though it should be noted that a few percent errors translate to a lot of energy, about the same amount that is causing all the concern.

On 14 January the Guardian had the headline, “Ocean temperatures hit record high as the rate of heating accelerates.” The study that reached this conclusion was published in the journal Advances in Atmospheric Sciences.

It’s a badly written paper full of self-justifying statements and unwarranted assumptions that should have been stripped-out by the editor.

 

Also : Ocean Warming: Not As Simple As Headlines Say

The Ocean Warms By A Whole Little

by Willis Eschenbach, January 4, 2020 in WUWT


How much is a “Whole Little”? Well, it’s like a whole lot, only much, much smaller.

There’s a new paper out. As usual, it has a whole bunch of authors, fourteen to be precise. My rule of thumb is that “The quality of research varies inversely with the square of the number of authors” … but I digress.

In this case, they’re mostly Chinese, plus some familiar western hemisphere names like Kevin Trenberth and Michael Mann. Not sure why they’re along for the ride, but it’s all good. The paper is “Record-Setting Ocean Warmth Continued in 2019“. Here’s their money graph:

 

Figure 1. Original Caption: “Fig. 1. (a) Upper 2000 m OHC from 1955 through 2019. The histogram represents annual anomalies (units: ZJ), wherein positive anomalies relative to a 1981−2010 baseline are shown as red bars and negative anomalies as blue. The two black dashed lines are the linear trends over 1955–86 and 1987−2019, respectively.”

 

So here’s the hot news. According to these folks, over the last sixty years, the ocean has warmed a little over a tenth of one measly degree … now you can understand why they put it in zettajoules—it’s far more alarming that way.

Next, I’m sorry, but the idea that we can measure the temperature of the top two kilometers of the ocean with an uncertainty of ±0.003°C (three-thousandths of one degree) is simply not believable.

Also Ocean Warming Scares

Also : New 80-Year Deep-Ocean Temperature Dataset Compared to a 1D Climate Model

Ocean acidification a big problem — but not for coral reef fish behavior

by Norwegian University of Science and Technology, Jan. 9, 2020 in WUWT


A three-year, comprehensive study of the effects of ocean acidification challenges previous reports that a more acidic ocean will negatively affect coral reef fish behaviour.

The study, conducted by an international coalition led by scientists from Australia and Norway, showed that coral reef fish exposed to CO2 at levels expected by the end of the century did not change their activity levels or ability to avoid predators.

“Contrary to previous studies, we have demonstrated that end-of-century CO2 levels have a negligible impact on the behaviour and sensory systems of coral reef fish,” said Timothy Clark, the lead author of the study and an associate professor at Deakin University in Australia.

Although this is good news on its own, ocean acidification and global warming remain a major problem for coral reefs, the researchers said. Ocean acidification is a problem for creatures that rely on calcium carbonate to make shells and skeletons, such as coral reef organisms, while higher ocean temperatures lead to coral bleaching and death.

..

New Paper: Ocean Temperature Changes Are Uneven And Uncertain

by DR.  B. Peiser, Nov. 8, 2019 in ClimateChangeDispatch


A new paper from the Global Warming Policy Foundation looks at how scientists monitor changes in ocean temperatures and finds a story of huge uncertainties and surprising findings.

For example, while warming might be expected to be fairly uniform, measurements suggest that it is regionalized, with parts of the South Pacific, in particular, warming more than elsewhere.

As the report’s author, Dr. David Whitehouse, says, it is hard to draw firm conclusions about what is happening in the seas:

“The oceans can absorb far more heat than the atmosphere, so temperatures changes are extremely small and therefore hard to measure reliably.”

“The energy that would raise the temperature of the atmosphere by 4 degrees C would only raise the ocean temperature by thousands of a degree, barely detectable.”

“Measuring changes in the ocean heat content are at the limits of our current capability and are made with significant uncertainties and unknowns.”

A recent claim that warming of the oceans was accelerating had to be withdrawn after errors were found in its uncertainty estimates by an independent scientist.

Cold Water? The Oceans and Climate Change can be downloaded here (PDF)

Serious Errors In IPCC Ocean Report Revealed

by B. Peiser, October 11, 2019 in GWPF


London, 11 October: The Global Warming Policy Foundation (GWPF) has called on the Intergovernmental Panel on Climate Change (IPCC) to correct serious errors in its recent Special Report on the Ocean and Cryosphere in a Changing Climate.

In a letter to the IPCC, Dr Benny Peiser, the GWPF’s director, has highlighted a number of errors and misinterpretations in the IPCC’s report which are based, to a significant degree, on a flawed study which was recently retracted.

In his letter, Dr Peiser points out that the IPCC’s overall conclusion on ocean heat uptake

“is based to a significant degree on a paper by Cheng et al. (2019) which itself relies on a flawed estimate by Resplandy et al. (2018). An authors’ correction of this paper and its ocean heat uptake estimate was under review for nearly a year, but in the end Nature requested that the paper be retracted (Retraction Note, 2019).”

“While the [IPCC’s] conclusion that the rate of ocean heat uptake has increased in recent years may probably be right, the evidence you cite for there being ‘high confidence’ and ‘high agreement’ is rather doubtful due to your inclusion of flawed evidence of the retracted paper by Resplandy et al. (2018).”

What is more, there is also doubt about the IPCC’s conclusion that ocean heat uptake has been accelerating in recent years. According to its own report the overall ocean heat uptake between 0-2000 m was nearly 10% higher over 1993-2017 than over the second half of that period, 2005-2017, suggesting that OHU may have been declining slightly rather than accelerating over the last 25 years.

In light of these flaws, the GWPF is calling on the IPCC to correct the evident errors and reduce its confidence rating accordingly.

Letter to the IPCC (pdf)
https://www.thegwpf.org/content/uploads/2019/10/IPCC-letter-Oct2019.pdf?utm_source=CCNet+Newsletter&utm_campaign=67a9d80e1a-EMAIL_CAMPAIGN_2019_10_11_11_33_COPY_01&utm_medium=email&utm_term=0_fe4b2f45ef-67a9d80e1a-36415357&mc_cid=67a9d80e1a&mc_eid=b9fdc60fd9

A Second Look At Radiation Versus Temperature

by Willis Eschenbach, June 14, 2019 in WUWT


I kept going back and looking at the graphic from my previous post on radiation and temperature. It kept niggling at me. It shows the change in surface temperature compared to the contemporaneous change in how much energy the surface is absorbing. Here’s that graphic again:

 

Figure 1. From my previous post. It is a scatterplot showing the dependence of temperature on the total downwelling radiation (longwave plus shortwave) absorbed by the surface.

What I found botheracious were the outliers at the top of the diagram. I knew what they were from, which was the El Nino/La Nina of 2015-2016.

After thinking about that, I realized I’d left one factor out of the calculations above. What the El Nino phenomenon does is to periodically pump billions of cubic meters of the warmest Pacific equatorial water towards the poles. And I’d left that advected energy transfer out of the equation in Figure 1. (Horizontal transfer of energy from one place on earth to another is called “advection”).

And it’s not just advection of energy caused by El Nino. In general, heat is advected from the tropics towards the poles by the action of the ocean and the atmosphere. Figure 2 shows the average amount of energy exported (plus) or imported (minus) around the globe.

New Proxy Data Show Northern Europe Weather Variability In Sync With Natural Factors: Solar Activity, Oceanic Cycles

by J. Goslin in P. Gosselin, June 1, 2019 in NoTricksZone


Another new paper, which of course will be ignored by the government-funded IPCC because it contradicts claims CO2 drives climate, shows that natural factors dominated the earth’s climate variability.

A team of scientists led by Jerome Goslin have published a paper titled Decadal variability of north-eastern Atlantic storminess at the mid-Holocene: New inferences from a record of wind-blown sand, western Denmark in the journal Global and Planetary Change, suggesting climate variability is driven naturally.

Image: NASA, public domain

Climate change driven by solar and oceanic cycles

Not surprisingly, as evidenced by hundreds of other publications (which are entirely ignored by the IPCC), climate variability is indeed tied to solar activity and “internal atmospheric and oceanic modes”.

CO2 and ocean chemistry

by Dr. Daniela Mazza, May 18, 2019 in WUWT


Oceans cover about 71% of the earth surface, but their influence on climate change is not only due to high heat capacity of water , not only to the ocean’s water circulation, but to a fact which is widely underestimated : the pH (acidity level) of sea-water is substantially alkaline, ranging from 8.0 to 8.7 . This means that the balance between positive and negative ions is reached by accounting for OH,hydroxide ions, in a far larger amount in respect to H+ hydrogen ions.

The pH value higher than 7 allows seawater to dissolve and react huge amounts of CO2 , carbon dioxide, thus affecting the amount of this gas in the atmosphere by absorbing excess of it. To calculate this excess in respect to what would be the true equilibrium value in the air, all of the chemical reactions involved have to be simultaneously computed, accounting for their equilibrium constants, which in turn depend on temperature.

1 – CO2 (gas) + H2O <==> H2CO3* (H2CO3* is the sum of dissolved CO2 and H2CO3)

2 – H2CO3 <==> H+ + HCO3

3 – HCO3 <==> H+ + CO3– –

4 – H2O <==> H+ + OH

5 – Ca++ + CO3– – <==> CaCO3 (calcite)

6 – Ca++ + OH <==> Ca(OH)+

7 – Mg++ + OH <==> Mg(OH)+

 

Conclusions : CO2 is at 410 ppm far above the equilibrium value (315) , provided a standard seawater composition and an average ocean temperature of 17°C (taken from wikipedia). No doubt that solubility will force more CO2 to be stored in oceans . Moreover if we consider CaCO3 formation (seawater has overshot the solubility of this salt nearly 50 times but nucleation and growth are slow) still more CO2 will be stored by limestone.

El Niño Conditions Persist in the Pacific Ocean

by A. Watts, April 16, 2019 in WUWT


An El Niño that began to form last fall has matured and is now fully entrenched across the Pacific Ocean. Changes in sea surface temperatures (SSTs) brought about by an El Niño affect the atmosphere, resulting in distinctive changes in the rainfall pattern across the Pacific Basin. These changes show up as anomalies or deviations in NASA’s analysis of climatological rainfall.

As with a traditional El Niño, the effects from a Central Pacific El Niño can still spread to the U.S. Also, clearly visible in the NASA-generated monthly average rainfall was an area of heavy rain over the southeast coast of Africa associated with the passage of Cyclone Idai, which devastated the region with torrential flooding.

For more information about El Nino, visit: https://www.pmel.noaa.gov/elnino/definitions
Learn more about NASA’s Precipitation measurements: http://pmm.nasa.gov/trmm

Deep-water circulation changes lead North Atlantic climate during deglaciation

by F. Muschitiello et al., March 20, 2019 in Nature


Abstract

Constraining the response time of the climate system to changes in North Atlantic Deep Water (NADW) formation is fundamental to improving climate and Atlantic Meridional Overturning Circulation predictability. Here we report a new synchronization of terrestrial, marine, and ice-core records, which allows the first quantitative determination of the response time of North Atlantic climate to changes in high-latitude NADW formation rate during the last deglaciation. Using a continuous record of deep water ventilation from the Nordic Seas, we identify a 400-year lead of changes in high-latitude NADW formation ahead of abrupt climate changes recorded in Greenland ice cores at the onset and end of the Younger Dryas stadial, which likely occurred in response to gradual changes in temperature- and wind-driven freshwater transport. We suggest that variations in Nordic Seas deep-water circulation are precursors to abrupt climate changes and that future model studies should address this phasing.

Study: Much of the surface ocean will shift in color by end of 21st century

by Charles the moderator,  February 5, 2019 in WUWT


Climate-driven changes in phytoplankton communities will intensify the blue and green regions of the world’s oceans

From the Massachusetts Institute of Technology

Climate change is causing significant changes to phytoplankton in the world’s oceans, and a new MIT study finds that over the coming decades these changes will affect the ocean’s color, intensifying its blue regions and its green ones. Satellites should detect these changes in hue, providing early warning of wide-scale changes to marine ecosystems.

Writing in Nature Communications, researchers report that they have developed a global model that simulates the growth and interaction of different species of phytoplankton, or algae, and how the mix of species in various locations will change as temperatures rise around the world. The researchers also simulated the way phytoplankton absorb and reflect light, and how the ocean’s color changes as global warming affects the makeup of phytoplankton communities.

The researchers ran the model through the end of the 21st century and found that, by the year 2100, more than 50 percent of the world’s oceans will shift in color, due to climate change.

Climate change might not slow ocean circulation as much as thought

by Carolyn Grambling, January 31, 2019 in ScienceNews


New findings from an international ocean observing network are calling into question the long-standing idea that global warming might slow down a big chunk of the ocean’s “conveyor belt.” The first 21 months of data from sensors moored across much of the North Atlantic are giving new insight into what controls the strength of the Atlantic Meridional Overturning Circulation, a system of currents that redistributes heat around much of the Western Hemisphere.

German Scientists Back Findings By Gebbie et al 2019, Believe Climate CO2 Sensitivity Even “Likely To Be Lower” Than 1.3°C

by P. Gosselin, January 29, 2019 in NoTricksZone


A paper very worth reading from the USA from January 2019 in Science (Geoffrey Gebbie of the Woods Hole Oceanographic Institution/Peter Huybers of Harvard University, hereinafter GH19) is titled “The Little Ice Age and 20th-century deep Pacific cooling”.

It shows fascinating science.

The authors evaluated temperature measurements made in the deep sea by the famous expedition of the “HMS Challenger” in the 1870s. The ship sailed the Atlantic and Pacific, and probably provided the first data on the oceans down to depths of over 2000 meters. The recalibration of the old data alone is a work of art! What the paper found: The Pacific down in depths has cooled from 1870 to today, the Atlantic not.

Ocean Warming in Climate Models Varies Far More than Recent Study Suggests

by Roy Spencer, January 17, 2019 in GlobalWarming


I wanted to expand upon something that was mentioned in yesterday’s blog post about the recent Cheng et al. paper which was widely reported with headlines suggesting a newer estimate of the rate of ocean warming is 40% higher than old estimates from the IPCC AR5 report in 2013. I demonstrated that the new dataset was only only 11% warmer when compared to the AR5 best estimate of ocean warming during 1971-2010.

The point I want to reemphasize today is the huge range in ocean warming between the 33 models included in that study. Here’s a plot based upon data from Cheng’s website which, for the period in question (1971-2010) shows a factor of 8 range between the model with the least ocean warming and the model with the most warming, based upon linear trends fitted to the model curves:

Yearly ocean heat content (OHC) changes since 1971 in 33 models versus the recent Cheng reanalysis of XBT and Argo ocean temperature data for the surface to 2,000m layer. The vertical scale is in both ZettaJoules (10^21 Joules) and in deg. C (assuming an ocean area of 3.6 x 10^14 m^2). The Cheng et al. confidence interval has been inflated by 1.43 to account for the difference between the surface area of the Earth (Cheng et al. usage) and the actual ocean surface area.

Early 20th century global warming

by Judith Curry, January 25, 2019 in ClimateEtc.


A careful look at the early 20th century global warming, which is almost as large as the warming since 1950.  Until we can explain the early 20th century warming, I have little confidence IPCC and NCA4 attribution statements regarding the cause of the recent warming.

This is an issue that has long interested me.  Peter Webster wrote a previous post Mid 20th Century Global(?) Warming, which focused on the warm bump that culminated in the 1940’s.  My interest in this period was reignited while working on my report Sea Level and Climate Change.  Then, the recent paper by Zanna et al. discussed in Ocean Heat Content  Surprises further made the wheels turn.

In response to the Ocean Heat Content thread, David Appell posted a link to this paper on twitter:

The early 20th century warming: Anomalies, causes and consequences