Annual Meeting: Choose Your Own (Virtual) Path- way. Part 2: Weather Extremes and Climate Change

As we noted in the previous blog post, there are multiple ways to navigate an AMS Annual Meeting, even though we’re usually channeled into separate rooms devoted to parallel conferences, each focused on an area of specialization. But this year’s all-virtual conference, during the coming week, offers unusual prospects for hopping AMS21 logo L6186437 DESGD v7from conference to conference, with room to follow crosscutting themes. One of the most active such themes this year is the relationship of extreme weather to climate change.

The Conference on Climate Variability and Change is a natural home for such presentations; for example, the poster on “The Principal Reasons for the Observed Increase in Atlantic Hurricane and Named Storm Activity,” by  Conor I. McMenemie  and Karl Zeller with NiCE Research.

They write:

It is known that sea surface temperatures (SSTs) are a key component for energizing equatorial Atlantic storms. Similarly that the SSTs in the region which germinate such events are largely dependent upon the duopoly of the surface temperature of the ocean currents flowing towards the equatorial Atlantic and the heating effect applied by the sun. There has been a significant loss of cloud cover. This has allowed for a corresponding increase in isolation, resulting in the increased SSTs which gives rise to the increased Named Storm and Hurricane activity. …a reduction in the frequency of the African Easterly Wave (AEW) weather system has allowed for an additional multi hundred terrawatt ocean heating effect, which is providing the additional ‘fuel’ for the storm and hurricane events. … The factors affecting the original precursors to the AEW system can be backtracked to the Ethiopian Highlands, where the confluence of a number of atmospheric events had given rise to this AEW climatic chain reaction. It will be suggested here that human activity had unintentionally made sufficient alteration to one of these precursors, in an area of uncommon meteorological vulnerability during the hurricane season. That as a consequence we had inadvertently degraded one of the planet’s major weather systems, which after being allowed to go unnoticed since the start of the last century, this is the principal reason for the observed increase in Atlantic Hurricane and Named Storm activity.

Another poster, by Emily Beros-Hickey and Christina M. Patricola ((Lawrence-BerkeleyNational Lab) in the same Wednesday session is on “Anthropogenic Influences on African Easterly Waves,” with potential insights on late 21st century Atlantic tropical cyclone climatology.

Anna M. Wilson et al  present a related poster in the same conference: “Efforts to Build Infrastructure Resiliency to Future Hydroclimate Extremes.” In their, they state:

Record-breaking storms are increasing in frequency with climate change. Aging infrastructure, increasing population, and land use changes are all exacerbating the impacts of these events on the human enterprise. Thus, infrastructure’s risk and resilience to unexpected events are changing in ways that we have not been yet able to precisely quantify. [We] highlight successful interdisciplinary efforts led by the water management community to reduce risk and build infrastructure resilience to an increasing frequency and complexity of events.

But not all the presentations in this crosscutting theme of weather extremes set in the context of climate change are in the same conference. For example Elizaveta Malashenko and Matt Rogers (McKinsey and Company) present a poster in the Conference on Weather, Climate, and the New Energy Economy about “Climate Risk and Response: Why, and How, Utilities Should Start to Manage Climate Change Risk.” They write:

The Fourth National Climate Assessment, released in late 2018, … predicted “more frequent and intense extreme weather and climate-related events,” such as floods and hurricanes. For utilities, the assessment concluded, the possibilities were grave: lower efficiency, higher expenses, and more power outages—even as demand for energy rises. And many utilities are not ready … The cost of extreme weather is already high, and the frequency and the cost to life and property of extreme weather events has increased in recent years. …Even now, some utilities are making investments in long-lived assets in risky locations, increasing system vulnerability and balance-sheet risk. On that basis, we believe there is a strong case for utilities to start now to take steps on climate-change adaptation.

In other ways, too, utilities are already more vulnerable to extreme weather events than in the past. When homes are built in areas prone to wildfires, power companies follow, placing their own assets at higher risk. These can even exacerbate the problem, if sparks from power lines ignite [wildfires]. …

If climate change brings significant sea-level rise, as many models predict, that raises new vulnerabilities, but the risk is material today. In the United States, nine nuclear-power plants are located within two miles of the ocean. Many of the nation’s 8,625 power plants were deliberately sited near shorelines in order to have access to water. As a result, when hurricanes strike, power plants already face significant flooding damage. … 44 power plants were in flooded areas in Hurricane Irene and 69 were in flooded areas in Hurricane Sandy. … During Houston’s Hurricane Harvey in 2017, wind and catastrophic flooding knocked down or damaged more than 6,200 distribution poles and 850 transmission structures; 21.4 gigawatts of generation were affected by wind damage, flooding damage, fuel supply issues, or evacuations and shutdowns. If sea levels rise, storm surges would hit further inland, causing more damaging coastal flooding to generation, transmission, and distribution infrastructure.

We examined the financial records of ten large power utilities in seven states where hurricanes are common plus New Jersey, where hurricanes are less common but dense coastal populations mean damage from storms can be particularly costly. According to this analysis, a typical utility saw $1.4 billion in storm-damage costs and lost revenues due to outages caused by storms over a 20-year period [and] using estimates from the Fourth National Climate Assessment for increases in extreme weather events and coastal infrastructure damage driven by climate change, we estimated that by 2050, the cost of damages and lost revenues would rise by $300 million. We estimate it would take $700 million to $1 billion for a typical Southeastern US utility to prepare for impacts related to climate change [and] … our conclusion is that it pays to prepare for extreme weather.

At the Symposium on the Coastal Environment, Chia-Ying Lee (Lamont–Doherty Earth Observatory) et al. use historical and future climate warming scenarios and downscaled modeling to generate model storms. A new, machine-learning based wind reconstruction model will be used with the model tropical cyclone tracks to assess the wind hazard in New York State and … estimate storm surge.

In the Conference on Hydrology, Eunsang Cho (Univ. of Maryland) et al. present on whether we should expect Slower or Faster Extreme Snowmelt in a Warmer World. Their findings indicate that so far such flood-producing events are less frequent in the western mountains but more frequent in the north-central states.

In the Symposium on Societal Applications, John Lee is presenting “Applications of Extreme Event Attribution: Climate Change Litigation and More.” His abstract explains:

As the science underlying extreme event attribution (EEA) continues to improve … EEA … will play an increasing role … in climate change litigation, both domestically and internationally. Causation, legally defined as the relationship between an event and a particular result, is a key component in such litigation. In other words, in this context, how can you prove that a defendant’s actions are sufficiently related to anthropogenic climate change such that the defendant can be held liable for damages that occur at a distant location? EEA addresses that question. EEA also is playing an increasingly important role in the insurance industry … to model and … prepare for future losses. As the climate changes, human rights impacts, from military conflict to forced migrations, become increasingly likely. EEA has an important role to play in the characterization and prediction of such environmental human rights abuses … [among other examples] … providing an additional tool to aid in mitigating these events.

Also in the conference on Climate Variability and Change, Ni Dai and Brian Soden (Univ. of Miami, FL) investigate the implications of climate change for tropical precipitation extremes. They point out that:

It is widely believed that precipitation extremes will increase in response to a warming climate. In the absence of changes in atmospheric circulations, extreme precipitation is expected to increase in already-moist regions along a thermodynamical Clausius-Clapeyron scaling. However, within the tropics, the sensitivities inferred from observations are roughly twice as large, implying an unknown contribution from atmospheric dynamics. … We investigate the relationship between convective aggregation and precipitation and the role that convective aggregation plays in amplifying the response of frequency of tropical precipitation extremes to interannual surface warming. … Increases in large-scale convective aggregation contribute to roughly one-third of the increase in extreme precipitation occurrence to interannual warming by shifting moderate-to-heavy precipitation events to more extreme precipitation intensities. The linkages between convective aggregation and precipitation extremes considered here offer insights into their potential response to anthropogenic warming.

In the second session of “Major Weather Events and Impacts of 2020,” Blair Trewin (Bureau of Meteorology) et al. present on “Australia’s 2019/20 Summer of Extremes and Its Climate Drivers.”

They document the exceptional heat and drought underlying the year’s deadly conflagrations. But they also note:

Several key climate drivers contributed to the dry and warm conditions in 2019, despite limited signals from the El Niño-Southern Oscillation, typically a major driver of eastern Australian drought. The strongest signal on seasonal timescales was a very strong positive phase of the Indian Ocean Dipole (IOD). Positive IOD events are associated with an enhanced likelihood of below-average rainfall in winter and spring across much of Australia, especially the south.

A second major driver of abnormal conditions was a persistent negative phase of the Southern Annular Mode (SAM). Negative phases of SAM in spring and summer are associated with enhanced risk of dry conditions along the east coast of Australia. The major contributor to the negative SAM phase was a rare Sudden Stratospheric Warming event over the Antarctic which peaked in mid-September, causing an early breakdown in the polar vortex and equatorward movement of mid-latitude westerly winds. A delayed monsoon also contributed to an abnormally dry November and December in northern Australia. … The conditions of 2019-20 were without precedent in the Australian historical record. As the climate warms, the world is seeing more extreme events outside the range of previous historical experience, with the scale of the wildfires of 2020 in the western United States analogous in some ways to the preceding summer in Australia.

While the Southern annular mode figured in Australia’s extreme summer, in the Conference on Climate Variability and Change, Bradford S. Barrett (U.S. Naval Academy) et al. look at the relation of Northern Hemisphere extremes to Arctic climate change: in “Extreme Greenland Blocking and Moisture Transport under Arctic Amplification: Historical and Future Perspectives.” They note:

Recent changes in low-frequency atmospheric circulation around Greenland, including as a result of accelerating Arctic amplification, have increased sensible heat and moisture advection from the mid-latitudes into the region.We explored the frequency and seasonality of extreme Greenland blocking in both past and future climates. Our findings are analyzed in context of other work on extreme weather and climate events, and future work is suggested on the role of moisture transport in developing or sustaining blocks over Greenland.

Also in the Climate Variability and Change conference, Bin Fu (Environment Canada) et al. present a poster earth system model ensemble finding that “projected trends of North American extreme temperatures over the next half-century are likely very uncertain and need to be applied with caution.”

And again the same conference, Salvador del Cos Garza (City College of New York) et al. present a poster in which they note the devastating effects of the 135 mph gusts from Hurricane Maria that are unprecedented in Puerto Rico. They study the effect of a warming Climate on return periods of extreme wind and precipitation in the Caribbean using bias corrected GCM Models. They found that Hurricane Maria level wind gusts are likely to occur far more often, from a 400-year occurrence event in current climate to once in a century events by the year 2100. Rainfall had a similar effect where events whose rainfall intensity occurred once every 500 years in observation are turning into once a century events. They conclude:PR Wind Gusts Return

The increase of wind speed and precipitation may be directly linked to the increase of Sea Surface Temperatures (SST) as a key driving force of Caribbean climate change and a strong indicator of extreme events. Current trends of SSTs are in the order of 0.15⁰C/decade, while future trends appear to accelerate to 0.7⁰C/decade at the end of the Century. The increased rate of occurrence of extreme events will negatively affect the longevity of the physical infrastructure.

Next Up Post 2 FinalWe have additional presentations detailing a variety of aspects connecting extreme weather to climate change, so check back in with this post as we approach the Annual Meeting. You also will want to check The Front Page for new posts highlighting other salient crosscutting themes, the struggle for social justice and equity, and citizen science.

 

 

The 101st AMS Annual Meeting: Find Your (Virtual) Pathway of Major Themes

We’re on the verge of the first ever all-virtual AMS Annual Meeting—yet another milestone in a time of milestones, but nonetheless our 101st Annual Meeting. And like all of the mega-gatherings AMS has held for the weather, water, and climate community in the past, this coming week (starting Sunday, January 10th), promises many opportunities to catchAMS21 logo L6186437 DESGD v7 up with what colleagues have been doing over the past year, what they’re thinking about now, and what they’re planning for coming years.

Although we’ll miss the chance encounters, side conversations, and in-person meet-ups, this year’s virtual format offers a lot of interaction with its breakout rooms and ample time set aside both for concentrated contemplation of presentations and for back-and-forth between presenters and audiences. Indeed, the fact that thousands of people are not all in one place attending parallel tracks of conferences and symposia with walls in-between them means that it may even be easier than ever to hop between sessions without running from room to room.

This Year’s Overarching Theme

The virtual experience may create an opportunity to take in multiple perspectives on the 101st Annual Meeting theme: this AMS tradition of organizing all the parallel conferences together on one unifying theme can come alive with the new format if you’re willing to navigate your own pathway through the presentations with that in mind. This year’s theme is “Strengthening engagement with communities through our science and service.” While on the face of it that theme has the spirit of many Annual Meeting themes of the past, in this meeting those words have more direct relevance on the programming than you may think. We’ll show you how with an upcoming blog post.

In fact, this year’s theme is pivotal for a meeting at this moment. It turned out to anticipate central issues of the year we had in 2020 and the directions and solutions your colleagues are proposing in their presentations, in response to the unique experience of 2020. In an forthcoming post, we’ll lay out these thematic implications by proposing a simple crosscutting pathway through the week’s video presentations, touching on the meeting theme by hopping from symposium to symposium, taking advantage of the Annual Meeting as a virtual experience.

The usual way most of us approach the meeting, of course, is to focus on an area of specialization. That’s why it is organized as always as a collection of about 40 specific conferences and symposia running in parallel—for example the 35th Conference on Hydrology, the 30th Conference on Education, and the 23rd Conference on Atmospheric Chemistry.

But you can imagine many independent, personalized ways to navigate any AMS Annual Meeting, such as a focus on multidisciplinary work, or on award winners’ presentations. In the following blog posts, we’ll dream up a few such tracks for you to take next week.

A Closer Look

Most years, attendees look forward to the AMS Annual Meeting as a chance to catch up on what colleagues have been accomplishing. In 2020, as in any normal year, it’s the major weather events of the past year that shape the work this community does. So as our first example of a pathway through the virtual meeting—think of it as a personalized symposium—we’ll focus on how the Annual Meeting is an opportunity to reflect collectively on 2020 weather and the lessons learned from studying it and forecasting it, and helping the world respond to it. As in the past, the Annual Meeting next week offers a targeted discussion of the past year’s weather, in particular in a symposium on Major Weather Events and Impacts of 2020. These sessions are on Friday, January 15. Among the events covered will be the August Midwest Derecho, high-impact atmospheric rivers, a North Dakota blizzard, the hyperactive 2020 hurricane season, wildfires, atmospheric effects of COVID, and all the 10 separate billion-dollar weather disasters (tying a record number) of the year in the United States (as charted here in historical context from Adam Smith’s abstract).

US Billion Dollar Disasters

Given the profusion of major disasters, all the papers about the year are not contained in one set of sessions or one conference. You can make 2020’s weather a multi-conference track through the meeting, if you’re so inclined. 2020 was that kind of year, of course! For example …

  • Also in the mesoscale symposium posters is an evaluation of the difficulty to forecast the August Midwest derecho, by Bruno Z. Ribeiro (SUNY Albany), Steven J. Weiss (SPC), and Lance Bosart (SUNY Albany). They write in their abstract: “This case demonstrates that improvements in the predictability of warm-season derecho-producing MCSs requires better understanding of the evolution from disorganized convection into a linear MCS.

With wildfires, extreme heat, air quality…this presentation has the overwhelming feeling of simultaneous extreme events of 2020 wrapped up in a nutshell. Indeed, as the above NOAA graphic of billion-dollar disasters exemplifies, the experience of 2020 opened up as never before in the United States a public discourse about the relationship between climate change and vulnerability to extreme weather. Not surprisingly, the AMS Annual Meeting is going to offer many insights on this relationship. That’s yet another thread you can follow as from symposium to symposium you try to personalize the virtual experience of the meeting, We’ll propose that pathway in a follow-on blog post, and right after that we’ll trace several other cross-cutting themes in the Annual Meeting—themes you’d never have found so pervasive in any other years. The 2021 Annual Meeting is unique for the reasons that 2020 was unique.

More Cross-cutting Theme Tie-ins

Of course you’ll note the massive disruption of COVID as mentioned in Ahmaov’s presentation. The pandemic had more impacts than just on air quality, but we explore in a follow-on blog post how the pervasive theme of COVID is in itself a viable personalized crosscutting pathway through the 2021 Annual Meeting, as are some of the other salient societal themes of 2020—the fight against racism, the struggle for social justice and equity, and the response of the sciences toNext Up1 Post 1 such larger societal issues by seeking better community engagement—thereby making this year’s overarching meeting theme exceptionally timely. These pathways in the Annual Meeting trace the ways the tumultuous year 2020 has left an indelible mark on the weather, water, and climate community, as it did on all other people and professions and sciences.

Not Just in Their Heads: New Research Confirms Connection Between Weather and Chronic Pain

Stormy weather increases pain. That fact is actually good news for people suffering from chronic pain whose complaints are often dismissed by family, their friends, and even their doctors.

Speaking, and likely complaining, about the effect of weather on their pain for millennia, chronic pain sufferers finally have a large-scale scientific study to back up their claims. Its findings reveal that, at least in the United Kingdom where the research was conducted, days with higher pain levels correspond with lower pressure and its attendant adverse weather conditions, including higher humidity, precipitation and increased wind. Conversely, low pain days where fewer experience a pain event are dominated by higher pressure with weaker winds and drier air.

In “Weather Patterns Associated with Pain in Chronic-Pain Sufferers,” recently published in the Bulletin of the American Meteorological Society, author David Schultz of the University of Manchester’s Centre for Atmospheric Sciences and Centre for Crisis Studies and Mitigation, along with colleagues, detail their 15-month smartphone study, “Cloudy with a Chance of Pain.” The UK-wide initiative involved more than 10,000 participants suffering from chronic pain who used a special phone app daily to answer 10 questions about their level of pain, related symptoms, mood and physical activity, and other questions about their pain. GPS sensors in their phones enabled concurrent tracking of their location’s average weather conditions, pairing observations with their responses for analysis.

Using an epidemiological method to confine comparisons to individual participants, their research found on any given day that 16 percent of chronic-pain sufferers experience a pain event at least one level above their typical pain level, using a 5-point scale: “no pain,” “mild pain,” “moderate pain,” “severe pain,” and “very severe pain.” This increased to 23 percent on high pain days, and dropped to 10 percent on low pain days. Weather patterns, they found, explain part of the changes, modulating pain in people. It remains to be determined who suffers most, but Schultz et al. have confidence in the findings of the largest and longest-term study of its kind on the weather–chronic pain relationship.

“This result confirms the anecdotal evidence from the three-quarters of those who suffer from chronic pain who say that their pain levels are related to poor weather,” Schultz says in a video he produced to discuss the topic and the study’s findings. [See below.]

He notes that because prior research had inconsistent results and disagreement over findings, reactions to their research have been mixed, with both high praise and disdain.

“It’s perhaps not surprising that the public reaction to our study is one of two things: depending on who you listen to, people either thank us for showing what they already knew and giving support to their strongly held beliefs, or they say it was a waste of time and money because they already knew that poor weather was associated with their pain.”

By the very nature of the smartphone survey, Schultz notes that participants had the opportunity to really look at their pain and the conditions accompanying it. And with evidence in hand, the opportunity now exists for scientists to move toward forecasting such conditions in tandem with people’s pain levels to provide understanding in addition to potential welcome relief.

For people who suffer from chronic pain and believe weather influences their daily pain levels, scientists including them in the study and then conclusively demonstrating this relationship on a large scale gives their suffering meaning and validates their beliefs.

“We’ve received so many emails and tweets of support from those who participated telling us how much they appreciate being able to participate in a study like this where they actually felt their contributions were valued and they were contributing to answering a scientific question that was important to them personally.  And, we do value their contributions.”

An Anticipated Increase in Earth's Strongest Storms

GoniA little more than two weeks ago, Supertyphoon Goni blasted ashore in the Philippines with top sustained winds of 195 mph, becoming the strongest landfalling tropical cyclone on record. It topped STY Haiyan’s 190 mph land strike just seven years ago. With Hurricane Iota in the Caribbean explosively intensifying 100 mph in under 24 hours to reach Category 5 intensity Monday, it set a new record of five consecutive years of Cat 5 hurricanes in the North Atlantic tropical cyclone basin. Among the seven catastrophic hurricanes, starting with Matthew in 2016, were Dorian and Irma, packing 185 mph and 180 mph steady winds, respectively, with peak gusts well over 200 mph.
Goni is the latest formidable example of an increasing trend in tropical cyclone intensity. While Goni established a new landfall wind intensity record, Iota and other recent major hurricanes Eta, Zeta, and Delta set or challenged records for most intense hurricanes so late in the season.
PercentilesJames Elsner of Florida State University says this is to be expected. His research stated in 2008 that there was an upward trend in the intensity of the most intense tropical cyclones. Rising ocean temperatures, as theory predicted, were driving the trend. And with oceans continuing to warm along with Earth’s climate since then, Elsner anticipated the continuing upward trend. New research published in the Bulletin of the American Meteorological Society confirms his prediction, finding that another 3.5 to 4.5 percent increase in intensity has occurred with the strongest tropical cyclones during the period 2007-19.
Globally, all basins show upward trends, Elsner says, with the North Atlantic and Western North Pacific revealing the steepest and most consistent upticks.

An Anticipated Increase in Earth’s Strongest Storms

GoniA little more than two weeks ago, Supertyphoon Goni blasted ashore in the Philippines with top sustained winds of 195 mph, becoming the strongest landfalling tropical cyclone on record. It topped STY Haiyan’s 190 mph land strike just seven years ago. With Hurricane Iota in the Caribbean explosively intensifying 100 mph in under 24 hours to reach Category 5 intensity Monday, it set a new record of five consecutive years of Cat 5 hurricanes in the North Atlantic tropical cyclone basin. Among the seven catastrophic hurricanes, starting with Matthew in 2016, were Dorian and Irma, packing 185 mph and 180 mph steady winds, respectively, with peak gusts well over 200 mph.

Goni is the latest formidable example of an increasing trend in tropical cyclone intensity. While Goni established a new landfall wind intensity record, Iota and other recent major hurricanes Eta, Zeta, and Delta set or challenged records for most intense hurricanes so late in the season.

PercentilesJames Elsner of Florida State University says this is to be expected. His research stated in 2008 that there was an upward trend in the intensity of the most intense tropical cyclones. Rising ocean temperatures, as theory predicted, were driving the trend. And with oceans continuing to warm along with Earth’s climate since then, Elsner anticipated the continuing upward trend. New research published in the Bulletin of the American Meteorological Society confirms his prediction, finding that another 3.5 to 4.5 percent increase in intensity has occurred with the strongest tropical cyclones during the period 2007-19.

Globally, all basins show upward trends, Elsner says, with the North Atlantic and Western North Pacific revealing the steepest and most consistent upticks.

We May Be Able to Further Improve Hurricane Track Forecasts After All

ZetaZeta blossomed into the 11th hurricane of this hyperactive season Monday and its forecast track takes it ashore on the Gulf Coast by midweek. The National Hurricane Center (NHC) on Monday said computer models had become more tightly clustered with the forecast in the Gulf, “resulting in an increase in track-forecast confidence,” and Hurricane Zeta is expected to become the United States’ record 11th storm landfall in a single season.

Such confidence is a reflection that NHC’s tropical storm and hurricane track forecasts, which go out 5 days, have substantially improved in the last 25 years. But, a 2018 essay in the Bulletin of the American Meteorological Society (BAMS) found that such improvements in track forecasts have slowed, raising concern about making them any better and extending them out beyond 5 days with any skill. While that study suggested improvements may have reached a limit, new research also published in BAMS finds a way to further refine them in the coming decades. Using a different interpretation of track position errors than the earlier article, the research moves the predictability limit for tropical cyclones out a day per decade to 6-8 days in the next 10-30 years.

Online Climate Science Course Keys Success to Frequent Forum Discussions

While colleges pre-COVID-19 were already designing and implementing courses for online instruction, the pandemic has pushed entire academic course offerings into this rapidly evolving virtual environment. A new article in the Bulletin of the AMS about an online climate science course for undergraduates, which was developed, offered, and honed to near-perfection based on postcourse surveys before coronavirus, provides this tip for virtual success: Have students engage each other often, one-on-one, in a discussion forum. The result, the instructors are finding, is improved comprehension, with a high percentage of students successfully absorbing and accurately communicating course material.

The online course is titled, “Climate and Climate Change,” and has been offered through the Department of Atmospheric and Oceanic Sciences (AOS) at the University of Wisconsin—Madison since 2013. “Students enrolled in this course learn the physical principles governing Earth’s climate and climate change within the broader context of societal impacts and global political considerations,” writes lead author Andrew M. Dzambo and colleagues in the article.

The goal, they write, is to improve student science literacy and address misconceptions by implementing a key learning tool: “the weekly discussion forum where students engage with each other while testing their own knowledge.” The result is an increased knowledge of climate science and the Earth-climate system, as the surveys showed.

The course—AOS 102—has been improved since its inception, and it grew in popularity when it was moved to summer semester in 2016. It expanded its capacity in 2018 to accommodate a growing waitlist of interested students. The course is delivered through weekly worksheets, quizzes, and a final project, but it’s the weekly forum discussions that instructors credit with students’ retaining and being able to discuss climate science.

In their article, the authors present a template of the course for implementation with other atmospheric or Earth-related science coursework:

Although the discussion forums were monitored by course instructors, every student engaged other students at least once a week and freely expressed their own fact-based feedback to one another. By having the majority of the weekly course grade centered around discussion forums and worksheet assignments, complemented with weekly quizzes and an independent final project, the majority of students leave the class with a fundamental understanding of climate science (as evidenced by the course surveys) and with the confidence that they feel well informed about climate change.

Syllabus

"Sleep with your phone on!": Messaging for Nighttime Tornadoes

With Hurricane Delta poised to strike Louisiana today, the risk of embedded tornadoes will increase as rainbands spiral ashore, along with the primary threats of storm surge and damaging winds. Delta is forecast to plow well inland Friday night into the weekend, continuing a low risk for tornadoes, some of which could occur at night in Alabama, Mississippi and into southern Tennessee. The threat is more than a bit worrisome as new research in BAMS finds through phone surveys and followup interviews in Tennessee that people are woefully unprepared for nocturnal tornadoes.
In their article,” Kelsey Ellis and colleagues found a host of poor practices by residents when it comes to tornadoes at night. The authors recommend forecasters narrow their messaging about nocturnal tornadoes in the Southeast to a single important message to limit confusion.
Almost half of Tennessee’s tornadoes occur at night, as in other Southeast states with large numbers of nocturnal tornadoes, and are two-and-a-half times as deadly as daytime tornadoes. This creates detection, warning, and public response challenges. Yet, respondents in the western part of the state overestimated tornado occurrence at night while those in the east substantially underestimated the number.
Additionally, nearly half of participants in the survey say they rely on sirens to receive tornado warnings. This is despite the fact that sirens are not designed to warn people inside nor be loud enough to wake anyone up. Instead, Wireless Emergency Alerts (WEAs) “should be a constant,” the authors say. Also, people mentioned they rely on TV and social media for receiving warnings even though generally neither will wake you up.
The authors felt it was “dangerous” that even the more tech savvy and tornado aware respondents answered they were compelled to look outside for evidence of a tornado—even in the dark. Interviewees explained they were “checking for sounds instead of visual cues.”
NWS forecasters were also surveyed about nocturnal tornadoes. The forecasters mentioned the lack of ground truth and fear for public safety among challenges to the nighttime warning service. They noted few spotter or social media reports inform them if “the storm is actually showing the signs on the grounds that radar is indicating aloft.” Forecasters said they felt “fearful, worried, or nervous for the public during nocturnal tornadoes because fatalities ‘are a given.’”
The survey responses moved Ellis et al. to recommend a single-emphasis message be presented to residents to combat the nighttime tornado problem:

One strategy that may improve public safety during a nocturnal tornado event, and which addresses the forecaster challenge of communication prior to and during an event, is to develop “One Message”—a consistent message that EMs and the media use throughout broadcasts, briefings, and social media. Examples of messages could be: “Nighttime tornadoes expected. Sleep with your phone ON tonight!” or “Tornadoes will form quickly! Make plans now where you will take shelter!” or “If you live in a manufactured home, you may not have much time to seek shelter tonight!” One Message may decrease confusion for receivers, making them more likely to make safe decisions. Messages could similarly be used to dispel misconceptions about local geography in ways relevant to the specific listening area, for example: “You are not protected by nearby hills. Seek shelter immediately!”

With Hurricane Delta’s nighttime tornado threat ramping up, the authors suggest people use multiple ways to receive warnings, keeps phones on and charged, don’t rely on tornado sirens, and if possible relocate ahead of the weather from “particularly vulnerable” situations, such as mobile homes and vehicles.

“Sleep with your phone on!”: Messaging for Nighttime Tornadoes

With Hurricane Delta poised to strike Louisiana today, the risk of embedded tornadoes will increase as rainbands spiral ashore, along with the primary threats of storm surge and damaging winds. Delta is forecast to plow well inland Friday night into the weekend, continuing a low risk for tornadoes, some of which could occur at night in Alabama, Mississippi and into southern Tennessee. The threat is more than a bit worrisome as new research in BAMS finds through phone surveys and followup interviews in Tennessee that people are woefully unprepared for nocturnal tornadoes.

In their article,” Kelsey Ellis and colleagues found a host of poor practices by residents when it comes to tornadoes at night. The authors recommend forecasters narrow their messaging about nocturnal tornadoes in the Southeast to a single important message to limit confusion.

Almost half of Tennessee’s tornadoes occur at night, as in other Southeast states with large numbers of nocturnal tornadoes, and are two-and-a-half times as deadly as daytime tornadoes. This creates detection, warning, and public response challenges. Yet, respondents in the western part of the state overestimated tornado occurrence at night while those in the east substantially underestimated the number.

Additionally, nearly half of participants in the survey say they rely on sirens to receive tornado warnings. This is despite the fact that sirens are not designed to warn people inside nor be loud enough to wake anyone up. Instead, Wireless Emergency Alerts (WEAs) “should be a constant,” the authors say. Also, people mentioned they rely on TV and social media for receiving warnings even though generally neither will wake you up.

The authors felt it was “dangerous” that even the more tech savvy and tornado aware respondents answered they were compelled to look outside for evidence of a tornado—even in the dark. Interviewees explained they were “checking for sounds instead of visual cues.”

NWS forecasters were also surveyed about nocturnal tornadoes. The forecasters mentioned the lack of ground truth and fear for public safety among challenges to the nighttime warning service. They noted few spotter or social media reports inform them if “the storm is actually showing the signs on the grounds that radar is indicating aloft.” Forecasters said they felt “fearful, worried, or nervous for the public during nocturnal tornadoes because fatalities ‘are a given.’”

The survey responses moved Ellis et al. to recommend a single-emphasis message be presented to residents to combat the nighttime tornado problem:

One strategy that may improve public safety during a nocturnal tornado event, and which addresses the forecaster challenge of communication prior to and during an event, is to develop “One Message”—a consistent message that EMs and the media use throughout broadcasts, briefings, and social media. Examples of messages could be: “Nighttime tornadoes expected. Sleep with your phone ON tonight!” or “Tornadoes will form quickly! Make plans now where you will take shelter!” or “If you live in a manufactured home, you may not have much time to seek shelter tonight!” One Message may decrease confusion for receivers, making them more likely to make safe decisions. Messages could similarly be used to dispel misconceptions about local geography in ways relevant to the specific listening area, for example: “You are not protected by nearby hills. Seek shelter immediately!”

With Hurricane Delta’s nighttime tornado threat ramping up, the authors suggest people use multiple ways to receive warnings, keeps phones on and charged, don’t rely on tornado sirens, and if possible relocate ahead of the weather from “particularly vulnerable” situations, such as mobile homes and vehicles.

Welcome to the Sticky Skies: Costlier Air Travel in a Warmer, Wetter World

COVID-19 has upended air travel for now, but if the growth in global aviation resumes, one real drag on flying is going to be increasing energy needs due to global warming. New research published in the Bulletin of the American Meteorological Society by Diandong Ren (Curtin University, Perth) et al. shows that Earth’s warming climate is going to have an often overlooked—but costly—impact on the fuel consumption of airplanes. The reason: increased viscosity, or “stickiness,” of the air.

For starters, a warming atmosphere will expand and become less dense, reducing the lift produced by aircraft wings, which means planes must increase speed and burn more fuel to maintain carrying capacity. This disadvantage counteracts any fuel advantages of flying in thinner (less resistant) air. There are other small effects on engine efficiency. In all, there is some ambiguity about the direct effect of the warming atmosphere on fuel needs at cruising altitudes. But Ren et al. point to a much larger fuel impact due to increasing atmospheric viscosity.

In a warmer world, more water can evaporate into the air. The extra molecules of water increase the drag on aircraft and that in turn will cause planes to fight harder to cruise through the air, requiring additional fuel. The increasing drag turns out to be the dominant issue—and could become very expensive.

Fuel increaseRen et al. use an ensemble of 34 climate models to project that aviation fuel requirements by the end of the century could be an extra 160 million gallons per year due to viscosity, approaching an extra $1 billion per year in costs more than today in a scenario in which fossil fuel use is basically unabated.

The findings take account of regional and altitudinal variations in warming for different projections based on different amounts of emissions predicted. They also take into account the most trafficked flight paths, based on recent airline data. For example, some high altitude cooling at high latitudes would mitigate the effects of drag in near-polar routes, but few jets fly these paths. Flights at mid- to low-latitudes experience the biggest increases in drag—less than 2% per century, but enough to have  consequences in fuel usage. Overall, an air viscosity increase leads to about a 0.22% increase in fuel consumption by the year 2100 over 2010.

While these costs are still a small fraction of the total aviation fuel usage, they are yet another incentive for the industry to mitigate global warming through emissions reductions, as well as to pursue adaptations and efficiencies in aviation technology.