Archives par mot-clé : Pacific

better to know...?, biology+acidification

Pacific coral reef shows historic increase in climate resistance

by Newcastle University, Aug 22, 2023 in EurekAlert

Coral reefs in one part of the Pacific Ocean have likely adjusted to higher ocean temperatures which could reduce future bleaching impacts of climate change, new research reveals.

A Newcastle University-led study focused on the Pacific Island nation of Palau and has shown that historic increases in the thermal tolerance of coral reefs are possible. The results demonstrate how this capacity could reduce future bleaching impacts if global carbon emissions are cut down.

Drawing on decades of field observations, the scientists modelled many possible future coral bleaching trajectories for Palauan reefs, each with a different simulated rate of thermal tolerance enhancement. They found that if coral thermal tolerance continues to rise throughout the 21st century at the most-likely historic rate, significant reductions in bleaching impacts are possible.

Published in the journal, Nature Communications, the results affirm the scientific consensus that the severity of future coral bleaching depends on carbon emissions reductions. High-frequency bleaching can be fully mitigated at some reefs under low-to-middle emissions scenarios where, for example, the Paris Agreement commitments are fulfilled. However, such bleaching impacts are unavoidable under high emissions scenarios where society continues to rely on fossil-fuelled development.

Study lead author, Liam Lachs, is a part of Newcastle University’s Coralassist lab. “Our study indicates the presence of an ecological resilience to climate change, yet also highlights the need to fulfil Paris Agreement commitments to effectively preserve coral reefs,” Lachs said. “We quantified a natural increase in coral thermal tolerance over decadal time scales which can be directly compared to the rate of ocean warming. While our work offers a glimmer of hope, it also emphasises the need for continued action on reducing carbon emissions to mitigate climate change and secure a future for these vital ecosystems.”

Study co-author, Dr James Guest, of Newcastle University’s School of Natural and Environmental Sciences, added: “We know that coral reefs can increase their overall thermal tolerance over time by acclimatisation, genetic adaptation or shifts in community structure, however we know very little about the rates at which this is occurring. This study uses data from a remote Pacific coral reef system and estimates the rate of increase in tolerance since the late 1980s. The results provide some hope that reefs can keep up with increasing temperatures, but only if strong action is taken on climate change.”

This study was the result of a collaborative visit the lead author undertook in 2021 to work with Professor Simon Donner’s Climate and Coastal Ecosystems Laboratory at the University of British Columbia, Canada. “This study shows the potential for some coral reefs to become more resilient to future climate change-fuelled heat waves,” Prof. Donner said. “That resilience, however, can also come at a cost, in terms of reduced reef diversity and growth. Without sharp cuts in greenhouse gas emissions over the next two to three decades, the reefs in the Pacific won’t provide the resources and protection from waves that Pacific peoples have depended upon for centuries.”

 

Continuer la lecture de Pacific coral reef shows historic increase in climate resistance →

climate-debate

Recent Shoreline Changes To Pacific Islands ‘Dwarfed’ By Change Magnitudes Of The Past

by K. Richard, Mar 6, 2023 in NoTricksZone

Most of the 1100 Pacific and Indian Ocean islands have been growing, not shrinking in size, in the last half century.

Activists convinced humans are able to exert fundamental control over ocean dynamics claim the rates of sea level rise and modern climate change are so rapid and unprecedented that modern changes are dramatically affecting shoreline movement on low-lying islands.

But a new study (Kench et al., 2023) assesses the opposite may be true. Recent shoreline changes (±40 m/50 years) are “dwarfed” by the shoreline changes (±200 m/100 years) that occurred throughout previous centuries. Globally, here is nothing “unprecedented” about what has been occurring with reef island shoreline dynamics in recent decades.

Of the global database of 1,100 Pacific and Indian Ocean reef islands, the “dominant mode of response has been the expansion of islands on reef surfaces (>53%)” over the last half-century. Only 0.3% (3 of 1,100) of islands have experienced “total loss.” Similarly, Duvat (2019) found 89% of 709 global-scale islands have been either stable or growing in size since the 1980s.

Of the islands sampled for the study, none are older than 1,400 years. Before then, they were submerged beneath the sea due to the much higher sea levels of the past.

…

climate-debate

Scientists Warn of a Rare Third Year La Nina

by INSTITUTE OF ATMOSPHERIC PHYSICS, CHINESE ACADEMY OF SCIENCES,  Oct 21, 2022 in WUWT

El Niño–Southern Oscillation (ENSO) is an irregular periodic variation in winds and sea surface temperatures over the tropical eastern Pacific Ocean that affects the climate of much of the tropics and subtropics. This natural phenomenon is important to study because of the socioeconomic impacts it can have on matters such as food security, agricultural production, human health and water resources, to name but a few.

With its strong preference to peak during boreal winter and rapidly decay in spring (known as “phase-locking”), and quasi-periodic oscillations of 2–7 years, historically, ENSO rarely maintains for long in either its cold phase (La Niña) or warm phase (El Niño). However, since the turn of the current century, three instances of so-called “double dip” La Niña events have occurred, in 2007–09, 2010–12 and 2020–22.

This succession of double-dip La Niña events is intriguing enough in itself; but now, based on updated data from several organizations issued in April 2022, it seems that the current event is likely to continue through the boreal summer and fall of 2022, suggesting a strong possibility of a third-year La Niña lasting from 202023.

“This would be the first third-year La Niña since the 1998–2001 event, which was the only such event observed since 1980,” explains Dr Xianghui Fang from Fudan University, China.

…

See also : Alarmist Scientist Tim Flannery’s Drought Prediction Contradicted… “Heavy Rainfalls” 3 Years In a Row

climate-debate

Pacific Typhoons Defy Climate Experts’ Dire Forecasts…Trending Downward 70 Years!

by P. Gosselin, Aug 6, 2022 in NoTricksZone

Pacific typhoons have been trending downward for 70 years 

The Japan Meteorological Agency (JMA) presents the latest data for Pacific typhoons — going back to 1951.

This summer climate alarmists in Europe have been chasing “heat waves”, likely because hurricanes and typhoons have been on the quiet side.

Today we look at the data from the Japan Meteorological Agency (JMA) for the number of typhoons formed in the Pacific in the month of July, now that the July data are available:

…

 

 

Clearly the world has warmed somewhat since 1951, but contrary to what the climate bedwetters claim, the trend in typhoons has been downward – suggesting that a warmer climate leads to less Pacific storms in terms of typhoons formed. This is the opposite of what climate “experts” said would happen.

Next we look at the number of typhoons formed in the Pacific from January to July, going back to 1951:

 

…

climate-debate

Was Global Warming The Cause of the Great Northwest Heatwave? Science Says No.

by C. Rotter, July 6, 2021 in WUWT

Reposted from The Cliff Mass Weather Blog

During the past week, the Pacific Northwest experienced the most severe heat event of the past century.

All-time high-temperature records were broken throughout the region, often by large margins. Many in the media, several local and national politicians, and some activist environmental scientists have claimed that this event was “driven by” or predominantly forced by human-inspired global warming (usually referred to as “climate change”).But such global warming claims are not supported by the facts and our best scientific understanding.  

Truth and Rigorous Science About Climate Change is Necessary for Wise Decisions
In this blog, I will use observations, modeling, climatological data, and the peer-reviewed scientific literature to demonstrate that human-caused global warming played a very small role in the extreme heat event that we just experienced here in the Pacific Northwest.I will describe the origins of a meteorological black swan eventand how the atmosphere is capable of attaining extreme, unusual conditions without any aid from our species.As you read this, consider that I have actively pursued research on Northwest heatwaves, published several papers in the peer-reviewed literature on this specific topic, and have run both weather prediction and climate models that simulate such events.  This subject is in my wheelhouse.

I also discuss the seriousness of misinformation.   You and others can not make wise decisions when the information provided to you is not based on truth and science.

…

climate-debate

Ice discharge in the North Pacific set off series of climate events during last ice age

by Oregon State University, Oct 1, 2020 in Science Daily

Repeated catastrophic ice discharges from western North America into the North Pacific contributed to, and perhaps triggered, hemispheric-scale changes in the Earth’s climate during the last ice age, new research published online today in Science reveals.

The discovery provides new insight into the impact rapidly melting ice flowing into the North Pacific may have on the climate across the planet, said Maureen Walczak, a paleoclimatologist in Oregon State University’s College of Earth, Ocean, and Atmospheric Sciences and the study’s lead author.

“Understanding how the ocean has interacted with glacial ice in the past helps us predict what could happen next,” Walczak said.

The Cordilleran ice sheet once covered large portions of western North America from Alaska to Washington state and western Montana. Radiocarbon dating and analyses of the marine sediment record revealed that recurrent episodes of discharge from this ice sheet over the past 42,000 years were early events in a chain reaction of disturbances to the global climate. These disturbances triggered changes in deep ocean circulation and retreat of ice sheets in the North Atlantic.

…

…

climate-debate

New Study: A Southern Ocean Site Has Just Cooled To Ice Age-Era Temperatures – 2°C Colder Than 20,000 Years Ago

by K. Richard, August 10, 2020 in NoTricksZone

A new temperature reconstruction indicates today’s sea surface temperatures are colder than all but a few millennia out of the last 156,000 years.

A Southern Ocean site analyzed in a new study (Ghadi et al., 2020) has averaged 1-2°C during glacials and 4°C during interglacials. Today, with a 410 ppm CO2 concentration, this location has again plummeted to glacial/ice age levels (2°C).

The site was 2°C warmer than now when CO2 concentrations were 180 ppm about 20,000 years ago, or during the peak of the last ice age. During the Early Holocene (10,000 to 8,000 years ago), summer sea surface temperatures were also 2°C warmer than today.

There is no indication that CO2 concentration changes are in any way correlated with temperature changes throughout this entire 156,000-year epoch.

better to know...?

Pacific Island states will not longer play the patsies for the climate alarmists

by P. Homewood, May 27, 2020 in NotaLotofpeopleKnowThat

The science is settled. The time for debate is over. It’s actually better than we thought. The Pacific islands are not sinking under rising sea levels, in fact, the peer-reviewed science shows the exact opposite, the majority of low lying islands are either stable or increasing in size — something even ABC FactCheck was forced to concede.

Nevertheless, this has not stopped climate alarmists led by the Portuguese socialist and UN General Secretary Guterres from denying the peer-reviewed science and exploiting Pacific Island nations, by using them as patsies to peddle fear and misinformation with discredited claims of ”sinking islands”.

And so far, the Pacific islanders have been happy to play along; perhaps driven by a cargo-cult mentality, believing if they utter the magic words ”climate change” and pose for the international media forlornly staring out over the sea, that they might be rewarded with cash handouts from the UN Green Global Climate fund.

But that was all before the Wuhan Flu.

…

biology+acidification, climate-debate

Coral tells own tale about El Niño’s past

by Rice University, March 27, 2020 in WUWT

HOUSTON – (March 26, 2020) – There is no longer a need to guess what ocean temperatures were like in the remote tropical Pacific hundreds of years ago. The ancient coral that lived there know all.

A study in Science led by Rice University and Georgia Tech researchers parses the record archived by ancient tropical Pacific coral over the past millennium. That record could help scientists refine their models of how changing conditions in the Pacific, particularly from volcanic eruptions, influence the occurrence of El Niño events, which are major drivers of global climate.

They found the ratio of oxygen isotopes sequestered in coral, an accurate measure of historic ocean temperatures, shows no correlation between estimates of sulfate particles ejected into the atmosphere by tropical volcanic eruptions and El Niño events.

That result could be of particular interest to scientists who suggest seeding the atmosphere with sun-blocking particles may help reverse global warming.

According to Rice climate scientist and primary author Sylvia Dee, previous climate model studies often tie volcanic eruptions, which increase sulfate aerosols in the atmosphere, to increased chances for an El Niño event. But the ability to analyze climate conditions based on oxygen isotopes trapped in fossil corals extends the climatological record in this key region across more than 20 ancient eruptions. Dee said this allows for a more rigorous test of the connection.

“A lot of climate modeling studies show a dynamical connection where volcanic eruptions can initiate El Niño events,” Dee said. “We can run climate models many centuries into the past, simulating volcanic eruptions for the last millennium.

“But the models are just that — models — and the coral record captures reality.”

Coral data that Georgia Tech climate scientist Kim Cobb and her team arduously collected on trips to the Pacific show little connection between known volcanoes and El Niño events over that time. Like tree rings, these paleoclimate archives hold chemical indicators, the oxygen isotopes, of oceanic conditions at the time they formed.

The coral data yields a high-fidelity record with a resolution of less than a month, tracking the El Niño-Southern Oscillation (ENSO) in the heart of the central tropical Pacific.

…

better to know...?, climate-debate

The ‘Little Ice Age’ hundreds of years ago is STILL cooling the bottom of Pacific, researchers find

by Charles the moderator, January 9, 2019 in WUWT

  • The Little Ice Age brought colder-than-average temps around the 17th century

  • Researchers say temperatures in deep Pacific lag behind those at the surface

  • As a result, parts of the deep Pacific is now cooling from long ago Little Ice Age

…

A Harvard study has found that parts of the deep Pacific may be getting cooler as the result of a climate phenomenon that occurred hundreds of years ago. The models suggest In the deep temperatures are dropping at a depth of around 2 kilometers (1.2 miles)