Climate Modellers Waiting for Observations to Catch Up with Their Predictions

Reblogged from Watts Up With That:

Eric Worrall / April 20, 2019

Guest essay by Eric Worrall

h/t Dr. Willie Soon; In climate science, when your model predictions are wrong, you wait for the world to correct itself.

New climate models predict a warming surge
By Paul VoosenApr. 16, 2019 , 3:55 PM

For nearly 40 years, the massive computer models used to simulate global climate have delivered a fairly consistent picture of how fast human carbon emissions might warm the world. But a host of global climate models developed for the United Nations’s next major assessment of global warming, due in 2021, are now showing a puzzling but undeniable trend. They are running hotter than they have in the past. Soon the world could be, too.

In earlier models, doubling atmospheric carbon dioxide (CO₂) over preindustrial levels led models to predict somewhere between 2°C and 4.5°C of warming once the planet came into balance. But in at least eight of the next-generation models, produced by leading centers in the United States, the United Kingdom, Canada, and France, that “equilibrium climate sensitivity” has come in at 5°C or warmer. Modelers are struggling to identify which of their refinements explain this heightened sensitivity before the next assessment from the United Nations’s Intergovernmental Panel on Climate Change (IPCC). But the trend “is definitely real. There’s no question,” says Reto Knutti, a climate scientist at ETH Zurich in Switzerland. “Is that realistic or not? At this point, we don’t know.”

…

Many scientists are skeptical, pointing out that past climate changes recorded in ice cores and elsewhere don’t support the high climate sensitivity —nor does the pace of modern warming. The results so far are “not sufficient to convince me,” says Kate Marvel, a climate scientist at NASA’s Goddard Institute for Space Studies in New York City. In the effort to account for atmospheric components that are too small to directly simulate, like clouds, the new models could easily have strayed from reality, she says. “That’s always going to be a bumpy road.”

…

In assessing how fast climate may change, the next IPCC report probably won’t lean as heavily on models as past reports did, says Thorsten Mauritsen, a climate scientist at Stockholm University and an IPCC author. It will look to other evidence as well, in particular a large study in preparation that will use ancient climates and observations of recent climate change to constrain sensitivity. IPCC is also not likely to give projections from all the models equal weight, Fyfe adds, instead weighing results by each model’s credibility.

…

Read more: https://www.sciencemag.org/news/2019/04/new-climate-models-predict-warming-surge

It’s nice to learn that the IPCC is considering using observations to constrain model projections.

Inconvenient stumps

Reblogged from Watts Up With That:

Anthony Watts / April 12, 2019

Climate alarmists tell us that the Earth has never been warmer, and that we can tell by looking at tree rings, treelines, and other proxy indicators of climate.

Climate scientists claim the warmth is unprecedented.

We’ve been told it is warming so fast, we have only 12 years left!

Yet nature seems to not be paying attention to such pronouncements, as this discovery shows.

This photo shows a tree stump of White Spruce that was radiocarbon dated at 5000 years old. It was located 100 km north of the current tree line in extreme Northwest Canada.

The area is now frozen tundra, but it was once warm enough to support significant tree growth like this.

If climate was this warm in the past, how did that happen before we started using the fossil fuels that supposedly made our current climate unprecedentedly warm?

A simple demo of order and chaos; Climate Models are not so simple

Here’s a fascinating example of oscillating systems.

In this demonstration 15 independent cyclic systems with different periods begin in phase, then watch how the total system departs from being in phase to apparent chaos to split phases and so on.

Now consider this demonstration as a model for all the contributors, big and small, to Earth’s climate–certainly more than the 15 billiard balls depicted here. And put the balls on springs of varying elasticity (permitting varying periods). And then allow the balls to hit each other (adding the third dimension to their oscillation and…..energy transfer).

Try to model and predict that!

Predicting heat waves? Look half a world away

Reblogged from Watts Up With That:

[HiFast Note:  This study identifies the Madden-Julian Oscillation (MJO) and correlates one of its phases to California heat waves.  Nothing really new here.  Joe Bastardi has been talking about the MJO for many years.]

charles the moderator / April 13, 2019

When thunderstorms brew over the tropics, California heat wave soon to follow

University of California – Davis

An orchard of young trees withstands drought in California’s Central Valley in 2014. The ability to predict heat waves in the Central Valley could help better prepare and protect crops and people from the impacts. Credit UC Davis

When heavy rain falls over the Indian Ocean and Southeast Asia and the eastern Pacific Ocean, it is a good indicator that temperatures in central California will reach 100°F in four to 16 days, according to a collaborative research team from the University of California, Davis, and the Asia-Pacific Economic Cooperation (APEC) Climate Center in Busan, South Korea.

The results were published in Advances in Atmospheric Sciences on April 12.

FROM PREDICTION TO PROTECTION

Heat waves are common in the Central California Valley, a 50-mile-wide oval of land that runs 450 miles from just north of Los Angeles up to Redding. The valley is home to half of the nation’s tree fruit and nut crops, as well as extensive dairy production, and heat waves can wreak havoc on agricultural production. The dairy industry had a heat wave-induced economic loss of about $1 billion in 2006, for instance. The ability to predict heat waves and understand what causes them could inform protective measures against damage.

“We want to know more about how extreme events are created,” said Richard Grotjahn, corresponding author on the paper and professor in the UC Davis Department of Land, Air and Water Resources. “We know that such patterns in winter are sometimes linked with areas of the tropics where thunderstorms are enhanced. We wondered if there might be similar links during summer for those heat waves.”

The scientists analyzed the heat wave data from June through September from 1979 to 2010. The data were collected by 15 National Climatic Data Centers stations located throughout the Valley. From these data, the researchers identified 24 heat waves. They compared these instances to the phases of a large, traveling atmospheric circulation pattern called the Madden-Julian Oscillation, or MJO.

The MJO manifests as heavy rain that migrates across the tropical Indian and then Pacific Oceans, and researchers have shown that it influences winter weather patterns.

TROPICAL RAINFALL AND CALIFORNIA

“It’s well known that tropical rainfall, such as the MJO, has effects beyond the tropics,” said Yun-Young Lee of the APEC Climate Center in Busan, South Korea, the paper’s first author. “So a question comes to mind: Is hot weather in the Central California Valley partly attributable to tropical rainfall?”

Lee and Grotjahn found that, yes, enhanced rainfall in the tropics preceded each heat wave in specific and relatively predictable patterns. They also found that hot weather in the valley is most common after more intense MJO activity in the eastern Pacific Ocean, and next most common after strong MJO activity in the Indian Ocean.

“The more we know about such associations to large-scale weather patterns and remote links, the better we can assess climate model simulations and therefore better assess simulations of future climate scenarios,” Grotjahn said.

###

This work was supported by the National Science Foundation, the National Aeronautics and Space Administration, the Department of Energy Office of Science, the United States Department of Agriculture’s National Institute of Food and Agriculture, and the APEC Climate Center in the Republic of Korea.

2019 ENSO forecast

Climate Etc.

by Judith Curry and Jim Johnstone

CFAN’s 2019 ENSO forecast is for a transition away from El Niño conditions as the summer progresses. The forecast for Sept-Oct-Nov 2019 calls for 60% probability of ENSO neutral conditions, with 40% probability of weak El Niño conditions. – Forecast issued 3/25/19

View original post 984 more words

2019 Hurricane season forecast: below average

Reblogged from Watts Up With That:

Anthony Watts / April 4, 2019

Dr. Philip Klotzbach of Colorado State University writes on Twitter:

Seasonal #hurricane forecast from @ColoradoStateU predicts slightly below-average season: 13 named storms, 5 hurricanes & 2 major (Cat 3+, >=111 mph) hurricanes. Primary reason for slightly below-avg forecast is anticipated continuation of weak #ElNino.

We anticipate that the 2019 Atlantic basin hurricane season will have slightly belownormal activity. The current weak El Niño event appears likely to persist and perhaps even strengthen this summer/fall. Sea surface temperatures averaged across the tropical Atlantic are slightly below normal, and the far North Atlantic is anomalously cool.

Our Atlantic Multi-decadal Oscillation index is below its long-term average. We anticipate a slightly below-average probability for major hurricanes making landfall along the continental United States coastline and in the Caribbean. As is the case with all hurricane seasons, coastal residents are reminded that it only takes one hurricane making landfall to make it an active season for them. They should prepare the same for every season, regardless of how much activity is predicted.

PROBABILITIES FOR AT LEAST ONE MAJOR (CATEGORY 3-4-5) HURRICANE LANDFALL ON EACH OF THE FOLLOWING COASTAL AREAS:

1) Entire continental U.S. coastline – 48% (average for last century is 52%)

2) U.S. East Coast Including Peninsula Florida – 28% (average for last century is 31%)

3) Gulf Coast from the Florida Panhandle westward to Brownsville – 28% (average for last century is 30%)

PROBABILITY FOR AT LEAST ONE MAJOR (CATEGORY 3-4-5) HURRICANE TRACKING INTO THE CARIBBEAN

(10-20°N, 88-60°W) 1) 39% (average for last century is 42%)

Abstract:

Information obtained through March 2019 indicates that the 2019 Atlantic hurricane season will have activity slightly below the 1981-2010 average. We estimate that 2019 will have about 5 hurricanes (average is 6.4), 13 named storms (average is 12.1), 50 named storm days (average is 59.4), 16 hurricane days (average is 24.2), 2 major (Category 3-4-5) hurricanes (average is 2.7) and 4 major hurricane days (average is 6.2).

The probability of U.S. major hurricane landfall is estimated to be about 90 percent of the long-period average. We expect Atlantic basin Accumulated Cyclone Energy (ACE) and Net Tropical Cyclone (NTC) activity in 2019 to be approximately 75 percent of their long-term averages. This forecast is based on an extended-range early April statistical prediction scheme that was developed using 29 years of past data.

Analog predictors are also utilized. For the first time, we are also using a statistical/dynamical model based off of data from the ECMWF System 5 as an additional forecast guidance tool. The current weak El Niño event appears likely to maintain intensity or perhaps even strengthen during the summer/fall. The tropical Atlantic is slightly cooler than normal, while the subtropical Atlantic is quite warm, and the far North Atlantic is anomalously cool.

The anomalously cold sea surface temperatures in the far North Atlantic lead us to believe that the Atlantic Multi-decadal Oscillation is in its negative phase. There is considerable uncertainty as to what the configuration of Atlantic sea surface temperatures will look like for the peak of the Atlantic hurricane season.

Coastal residents are reminded that it only takes one hurricane making landfall to make it an active season for them, and they need to prepare the same for every season, regardless of how much activity is predicted. The early April forecast is the earliest seasonal forecast issued by Colorado State University and has modest long-term skill when evaluated in hindcast mode. The skill of CSU’s forecast updates increases as the peak of the Atlantic hurricane season approaches.

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Source:
https://tropical.colostate.edu/media/sites/111/2019/04/2019-04.pdf

Solar slump continues – NOAA: “we are currently approaching a Maunder-type minimum in solar activity.”

Reblogged from Watts Up With That:

Anthony Watts / April 5, 2019

Solar experts predict the Sun’s activity in Solar Cycle 25 to be below average, similar to Solar Cycle 24

April 5, 2019 – Scientists charged with predicting the Sun’s activity for the next 11-year solar cycle say that it’s likely to be weak, much like the current one. The current solar cycle, Cycle 24, is declining and predicted to reach solar minimum – the period when the Sun is least active – late in 2019 or 2020.

Solar Cycle 25 Prediction Panel experts said Solar Cycle 25 may have a slow start, but is anticipated to peak with solar maximum occurring between 2023 and 2026, and a sunspot range of 95 to 130. This is well below the average number of sunspots, which typically ranges from 140 to 220 sunspots per solar cycle.

Graph via Twitter from
NOAA’s Space Weather Workshop

The panel has high confidence that the coming cycle should break the trend of weakening solar activity seen over the past four cycles.

“We expect Solar Cycle 25 will be very similar to Cycle 24: another fairly weak cycle, preceded by a long, deep minimum,” said panel co-chair Lisa Upton, Ph.D., solar physicist with Space Systems Research Corp. “The expectation that Cycle 25 will be comparable in size to Cycle 24   means that the steady decline in solar cycle amplitude, seen from cycles 21-24, has come to an end and that there is no indication that we are currently approaching a Maunder-type minimum in solar activity.”

The solar cycle prediction gives a rough idea of the frequency of space weather storms of all types, from radio blackouts to geomagnetic storms and solar radiation storms. It is used by many industries to gauge the potential impact of space weather in the coming years. Space weather can affect power grids, critical military, airline, and shipping communications, satellites and Global Positioning System (GPS) signals, and can even threaten astronauts by exposure to harmful radiation doses.

Solar Cycle 24 reached its maximum – the period when the Sun is most active – in April 2014 with a peak average of 82 sunspots. The Sun’s Northern Hemisphere led the sunspot cycle, peaking over two years ahead of the Southern Hemisphere sunspot peak.

Solar cycle forecasting is a new science

While daily weather forecasts are the most widely used type of scientific information in the U.S., solar forecasting is relatively new. Given that the Sun takes 11 years to complete one solar cycle, this is only the fourth time a solar cycle prediction has been issued by U.S. scientists. The first panel convened in 1989 for Cycle 22.

For Solar Cycle 25, the panel hopes for the first time to predict the presence, amplitude, and timing of any differences between the northern and southern hemispheres on the Sun, known as Hemispheric Asymmetry. Later this year, the Panel will release an official Sunspot Number curve which shows the predicted number of sunspots during any given year and any expected asymmetry. The panel will also look into the possibility of providing a Solar Flare Probability Forecast.

“While we are not predicting a particularly active Solar Cycle 25, violent eruptions from the sun can occur at any time,” said Doug Biesecker, Ph.D., panel co-chair and a solar physicist at NOAA’s Space Weather Prediction Center.

An example of this occurred on July 23, 2012 when a powerful coronal mass ejection (CME) eruption missed the Earth but enveloped NASA’s STEREO-A satellite.

Powerful eruption from the surface of the sun captured on May 1, 2013. NASA

A 2013 study estimated that the U.S. would have suffered between $600 billion and $2.6 trillion in damages, particularly to electrical infrastructure, such as power grid, if this CME had been directed toward Earth. The strength of the 2012 eruption was comparable to the famous 1859 Carrington event that caused widespread damage to telegraph stations around the world and produced aurora displays as far south as the Caribbean.

The Solar Cycle Prediction Panel forecasts the number of sunspots expected for solar maximum, along with the timing of the peak and minimum solar activity levels for the cycle. It is comprised of scientists representing NOAA, NASA, the International Space Environment Services, and other U.S. and international scientists. The outlook was presented on April 5 at the 2019 NOAA Space Weather Workshop in Boulder, Colo.

For the latest space weather forecast, visit https://www.swpc.noaa.gov/

Why climate predictions are so difficult

“The difficulties [in climate modeling Bjorn Stevens of the Hamburg Max Planck Institute for Meteorology] and his fellow researchers face can be summed up in one word: clouds. The mountains of water vapor slowly moving across the sky are the bane of all climate researchers.”

Climate Etc.

by Judith Curry

An insightful interview with Bjorn Stevens.

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Retreating Greenland glacier is growing again

Tallbloke's Talkshop

Jakobshavn glacier, West Greenland [image credit: Wikipedia]
Without jumping to hasty conclusions, this is an interesting development not predicted by the IPCC’s supposed experts. Natural ocean/climate oscillations are implicated. Against assumptions, rising carbon dioxide levels cannot explain these latest observations.

A new NASA study finds a major Greenland glacier that was one of the fastest shrinking ice and snow masses on Earth is growing again, reports The GWPF.

The scientists were so shocked to find the change, Khazendar said: “At first we didn’t believe it.

“We had pretty much assumed that Jakobshavn would just keep going on as it had over the last 20 years.”

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Hurricanes & climate change: 21st century projections

Climate Etc.

by Judith Curry

Final installment in my series on hurricanes and climate change.

View original post 4,485 more words