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Edmund Chang

Pixabay photo

By Daniel Dunaief

The weather outside has been frightful and local researchers suggest the trend has been anything but delightful.

Over the last year, the country has confronted numerous violent and intense storms, causing property damage and leading to evacuations and rescues. Just last week, Fort Lauderdale, Florida received a month’s worth of rain in an hour amid a storm that dumped over two feet of rain on the city. Such a torrential storm isn’t unique to Florida, as areas including Dallas experienced significant rains last August that crippled the city.

Malcolm Bowman

“The extremes are increasing,” said Malcolm Bowman, Professor Emeritus at the School of Marine and Atmospheric Sciences at Stony Brook University. “It’s part of the prediction of climate science.”

Indeed, as the atmosphere becomes warmer, the increase in water vapor raises the amount of rain in a particular storm, added Edmund Chang, Professor in the School of Marine and Atmospheric Sciences at Stony Brook University. Chang and other local scientists discussed their concerns and potential cause for optimism amid the approach of the 54th anniversary of Earth Day.

Climate Change report

This March, the Intergovernmental Panel on Climate Change (IPCC) released a report that suggested that climate change was worsening and that the Earth will likely increase by more than the 1.5 degrees Celsius above pre-industrial revolution averages that would lead to numerous environmental damage.

“Since the last IPCC report, there has been a lot more research looking at these weather extremes,” Chang said.

Edmund Chang

In warmer temperatures, which have increased on average for the Earth by 1.1 degrees, storms carry significantly more precipitation.

While it is outside the realm of his own research, Chang said that other researchers have demonstrated that storms in the Northeastern United States have had an increase in higher precipitation events, which is also linked to the fact that these storms are moving more slowly, drenching areas with rain before slowly leaving.

Chang is particularly concerned about sea level rise. “I have lived in coastal areas all my life,” he said. “We know that the sea level is rising. The rate of rise is accelerated.” Counteracting the effects of melting ice sheets in Greenland and the Antarctic are among the more difficult processes to mitigate, he added.

In his own research, Chang is assessing the bias in models that predict whether a season will likely be stormier than average. He is looking at how model biases may impact the accuracy of longer range forecasts.

Different models have different biases, he explained. Weather channel fans, and those who watch storm models for approaching hurricanes and other events, may recognize that meteorologists often overlay American and European weather models, particularly when describing approaching hurricanes.

In Chang’s research, he has found that combining different models improves the forecast. “A better way of improving models is to understand where the model biases or error comes from” rather than averaging errors that cancel each other out, he said.

Reasons for optimism

Chang believes there are reasons for optimism about efforts to mitigate the effects of climate change. The current administration is “starting to impose more stringent emissions controls from vehicles,” he said. “It’s getting a bit more encouraging.”

In other areas, world leaders have also taken encouraging steps towards protecting the oceans and biodiversity. Last month, the United Nations announced the legal framework for a High Seas treaty, which protects biodiversity, reduces pollutions and shares ocean resources. After 20 years of work, 193 countries verbally agreed to a treaty to protect 30 percent of the world’s oceans by 2030.

Ellen Pikitch

The treaty is “of monumental importance,” said Ellen Pikitch, endowed professor of Ocean Conservation Science and executive director of the Institute for Ocean Conservation Science at the School of Marine and Atmospheric Sciences at Stony Brook University. “The treaty will enable marine protected areas (MPAs) to be created in areas outside national jurisdictions and allow fisheries management of species in international waters not currently covered by regional agreements.”

Citing recent reports, Bowman said global emissions of carbon dioxide have declined 2 percent over the last 12 months. “There are moves, even in China, to bring in solar and wind” power, he added.

Local concerns

As storms hit areas like Florida and Texas, Long Islanders frequently wonder about the readiness of the region for future storms. Indeed, Hurricane Sandy wreaked havoc in the Middle Atlantic states in 2012.

“If we had another Sandy, it could be just as bad or worse,” said Bowman, who has been a part of a storm surge working group in New York.

In the fall, the Army Corps of Engineers published a tentatively selected plan for the area after the administration of President Biden (D) reinstated the Harbor and Tributary Study, which was temporarily halted in 2019. The plan doesn’t involve enough protection along the harbor with concrete and steel, Bowman said. 

“They say [concrete] is terrible,” Bowman said. “We say it’s necessary.”

Any plan for flooding in and around the New York area would not only have to address how to handle a storm surge that brought water in from the ocean. It would also have to provide a way for any heavy rains to get out.

The reality of global warming is “scary,” said Bowman. And yet, “how many people are changing their living habits?”

As for his native New Zealand, Bowman said a tornado touched down in recent weeks, which is “unheard of.” While the tornado was not on the scale of such twisters in Kansas, he said it ripped through several homes.

New Zealand, with a population of five million people, is moving toward using electric cars, while the country is also considering a genetic modification in cattle that reduces the production of methane from when they burp or pass gas.

“There’s a big push in New Zealand to do its bit,” Bowman said.

The temperatures at the poles are heating up more rapidly than those at the equator. Pixabay photo

By Daniel Dunaief

On any given day, heat waves can bring record-breaking temperatures, while winter storms can include below average cold temperatures or snow.

Edmund Chang. Photo from SBU

Weather and climate experts don’t generally make too much of a single day or even a few days amid an otherwise normal trend. But, then, enough of these exceptional days over the course of years can skew models of the climate, which refers to average temperature and atmospheric conditions for a region.

If the climate is steady, “we should see approximately the same number of hot and cold records being broken,” said Edmund Chang, Professor at the School of Marine and Atmospheric Sciences at Stony Brook University. “Over the past few decades, we have seen many more hot records being broken than cold records, indicating the climate is getting hotter.”

Recent heat

Indeed, just last week, before a heatwave hit the northeastern United States, the United Kingdom reported the hottest day on record, with the temperature at Heathrow Airport reaching above 104 degrees.

Erinna Bowman, who grew up in Stony Brook and has lived in London since 2009, said the temperature felt “like a desert,” with hot, dry heat radiating up in the urban setting. Most homes in London don’t have air conditioning, although public spaces like supermarkets and retail stores do.

“I’m accustomed to the summer getting quite hot, so I was able to cope,” said Bowman. Indeed, London is usually considerably cooler during the summer, with average temperatures around 73 degrees.

Michael Jensen. Photo from BNL

News coverage of the two extraordinarily hot days in London “was very much framed in the context of a changing climate,” Bowman said. The discussion of a hotter temperature doesn’t typically use the words “climate change,” but, instead, describes the phenomenon as “global heating.”

For climate researchers in the area, the weather this summer has also presented unusual challenges.

Brookhaven National Laboratory meteorologist Michael Jensen spent four years planning for an extensive study of convective clouds in Houston, in a study called Tracking Aerosol Convection Interactions, or Tracer.

“Our expectation is that we would be overwhelmed” with data from storms produced in the city, he said. “That’s not what we’re experiencing.”

The weather, which has been “extremely hot and extremely dry,” has been more typical of late August or early September. “This makes us wonder what August is going to look like,” he said.

Jensen, however, is optimistic that his extensive preparation and numerous pieces of equipment to gather meteorological data will enable him to collect considerable information.

Warming at the poles

Broadly speaking, heat waves have extended for longer periods of time in part because the temperatures at the poles are heating up more rapidly than those at the equator. The temperature difference between the tropics and the poles causes a background flow from west to east that pushes storms along, Chang explained.

The North Pole, however, has been warming faster than the tropics. A paper by his research group showed that the lower temperature gradient led to a weakening of the storm track.

When summer Atlantic storms pass by, they provide relief from the heat and can induce more clouds that can lead to cooler temperatures. Weakening these storms can lead to fewer clouds and less cooler air to relieve the heat, Chang added.

Rising sea levels

Malcolm Bowman. Photo from SBU

Malcolm Bowman, who is Erinna Bowman’s father and is Distinguished Service Professor at the School of Marine and Atmospheric Sciences at Stony Brook University, believes the recent ice melting in Greenland, which has been about 10 degrees above normal, could lead to a rise in sea levels of about one inch this summer. “It will slowly return to near normal as the fresh water melt spreads slowly over all the world’s oceans,” he added.

Bowman, who has studied sea level rises and is working on mitigation plans for the New York area in the event of a future major storm, is concerned about the rest of the hurricane season after the level of warming in the oceans this summer. 

“Those hurricanes which follow a path over the ocean, especially following the Gulf Stream, will remain strong and may gather additional strength from the heat of the underlying water,” he explained in an email.

Bowman is the principal investigator on a project titled “Long Island South Shore Sea Gates Study.”

He is studying the potential benefit of six possible sea gates that would be located across inlets along Nassau and Suffolk County. He also suggests that south shore sand dunes would need to be built up to a height of 14 feet above normal high tide.

Meanwhile, the Army Corps of Engineers has come up with a tentatively selected plan for New York Harbor that it will release some time in the fall. Bowman anticipates the study will be controversial as the struggle between green and grey infrastructure — using natural processes to manage the water as opposed to sending it somewhere else — heats up.

As for the current heat waves, Bowman believes they are a consistent and validating extension of climate change.

Model simulations

In his lab, Chang has been looking at model simulations and is trying to understand what physical processes are involved. He is comparing these simulations with observations to determine the effectiveness of these projections.

To be sure, one of the many challenges of understanding the weather and climate is that numerous factors can influence specific conditions.

“Chaos in the atmosphere could give rise to large variations in weather” and to occasional extremes, Chang said. 

Before coming to any conclusions about longer term patterns or changes in climate, Chang said he and other climate modelers examine collections of models of the atmosphere to assess how likely specific conditions may occur due to chaos even without climate change.

“We have to rule out” climate variability to understand and appreciate the mechanisms involved in any short term changes in the weather, he added.

Still, Chang said he and other researchers are certain that high levels of summer heat will be a part of future climate patterns. 

“We are confident that the increase in temperature will result in more episodes of heat waves,” he said.

Minghua Zhang

By Daniel Dunaief

Minghua Zhang spent a sabbatical year in China trying to improve climate models, which included analyzing errors of current models.

A professor at the School of Marine and Atmospheric Sciences at Stony Brook University, Zhang focused on the Southern Great Plains of the United States. He explored how the current models did not accurately simulate convection, which created a warm and dry bias.

In convection, heat and moisture get carried upward. The models account for summer rainfall but do not calculate the organizational structure of the convective systems, which led them to simulate insufficient precipitation.

By adding in the new information, Zhang predicts in recent research published in the scientific journal, Nature Communications, that the projected warming in the region would be 20 percent less than previously thought. Precipitation, meanwhile, would be about the same as it is today, instead of the drying that was previously anticipated.

“The resolution of the models is not high enough to predict the change of the convection with a high degree of precision,” Zhang explained in an email.

He suggested that using 10 times the specificity of model calculations, he expects a clearer picture of the likely climate by the end of the 21st century. This is like looking through binoculars at a nondescript moving shape in the distance. By adding focal power to the lens, the image can become sharper and clearer.

The climate is a big picture view of trends over the course of many years. That is distinct from weather, which involves day-to-day variations and which meteorologists describe each morning and evening with colorful images of cold and warm fronts on local maps.

“You have many things you can’t see and now you have better binoculars,” he suggested. “This tiny thing in the binoculars can make a bigger impact. What we see is that these [variables] actually matter.”

Zhang suggested that a climate model that better accounts for summer rainfall still includes higher temperatures in this sensitive region. “The warming is going to be there and will be significant,” he said. If carbon dioxide emissions continue at their current rate, the warming will still be about five degrees by the end of the century, he suggested. That, he predicted, will still have a significant impact on agriculture.

Edmund Chang, a professor at the School of Marine and Atmospheric Sciences at Stony Brook who was not involved in this study, said this research addresses “a specific bias of the model that needs to be taken care of.” He added that researchers know that the “models are not perfect” and suggested that the “scientific and climate modeling community is trying to refine and improve” these tools.

Chang agreed that the refinement “doesn’t change the fact that we still project a large increase in the temperatures over the central United States.”

The Southern Great Plains region has some unique elements that make climate predictions challenging. It has considerable organized convection, which increases the occurrence of tornadoes. There’s also a large coupling between the soil moisture and the clouds, which means that whatever happens on the land has feedback for the atmosphere.

Zhang said his research focus is on climate simulation modeling. He knew the models had problems simulating convective events, which is why he started exploring this specific region. “The way the models are constructed, the granules are not small enough,” he said.

Chang expected that this work would “spur more research on trying to understand this mechanism. Model developers will need to try to find out how to improve the physical model.”

Zhang has been working for the last two years with scientists from Tsinghua University in China, which included his time on sabbatical. “When you are on sabbatical, you have more time to really think about problems,” he said.

Chang added that sabbaticals can provide some time to focus on specific scientific questions. During a typical semester that includes administrative responsibilities and teaching, professors “are very busy,” He said. “We really don’t have an extended period of time to focus on one project. The sabbatical gives us a chance to focus.”

Zhang hopes this study “motivates people to think about how to improve their models in describing” other climate systems.

One of the many challenges scientists like Zhang face in developing these climate models is that their computers are still not powerful enough to resolve elements like clouds, which not only dot the landscape and provide shade during the summer but also send the sun’s energy back into space.

The system he’s studying is “chaotic by nature,” which makes accounting for elements that change regularly challenging. He suggested that these studies were akin to the butterfly effect. Scientists have suggested that someone who went back in time and committed a seemingly trivial act, like killing a single butterfly, might return to his familiar time and surroundings to discover profound changes.

While that’s an exaggeration, that’s still the kind of system he said researchers are confronting as they try to account for, and weigh, climate defining factors. That’s why he’s looking for statistical, or probabilistic, predictions that are averaged over time periods.

The United States, China and the European Union are all pursuing more powerful computers for these kinds of applications, Zhang said.

Zhang, who is the editor-in-chief of the Journal of Geophysical Research: Atmospheres, has been involved in an advisory capacity with the United States Department of Energy in developing these models. A

s for this specific effort, Zhang said he was pleased that the paper pointed out a research direction to refine models for climate in this area. “What we see is that these things [including convection] actually matter,” he said. “That’s the main contribution of this paper.”