A Minimum of Maximum Concern

There are a lot of questions about the current solar minimum, which has reached historic levels—“No solar physicist alive today has experienced a minimum this deep or this long,’’ according to NASA’s Madhulika Guhathakurta, lead program scientist for NASA’s Living With A Star program, which studies solar variability and its effects on Earth. Some of the effects of the minimum are fairly clear to scientists: the amount of cosmic rays entering our portion of the solar system is greater than normal, and Earth’s ionosphere has shrunk.

The solar minimum at an extreme: a spotless sun on July 1, 2008.

The debate is instead partly about the effect of the minimum on Earth’s climate. A recent study by Judith Lean of the Naval Research Lab and David Rind of NASA’s Goddard Institute for Space Studies suggests that decreased solar irradiance during the current minimum cycle may be slightly offsetting recent warming attributed to greenhouse gases. Even if the minimum is affecting climate, it may be of minimal consequence.
“. . . [O]nly about 10 percent of climate variation is due to the sun,” notes Leon Golub, senior astrophysicist at the Harvard-Smithsonian Institute for Astrophysics. “That means 90 percent isn’t.”
Just as importantly, the solar minimum won’t last forever, so any climatic effects are temporary, as well. But when will solar activity turn around? The current minimum began in 2000 and has been particularly deep for the last two years. At the AMS Annual Meeting, Joseph Kunches of NOAA’s Space Weather Prediction Center attempts to pinpoint the arrival of the next solar maximum and ponders its potential effects in his presentation, “Solar Cycle Update—Will the New Cycle Please Start?” (Monday, 2:15–2:30 p.m., B303). And Matthew J. Niznik and W. F. Denig of the National Environmental Satellite, Data, and Information Service introduce a new indicator, the Genesis Minimum Quiet Day Index, which analyzes sunspot activity and suggests that the current solar minimum is not anomalous. Their index and the larger topic of the influence of solar activity on Earth’s climate are explored in their poster, “Impacts of Extended Periods of Low Solar Activity on Climate” (Monday, 2:30–4:00 p.m., exhibit hall B2).

Harsh Cold Wave Slowly Retreating

Well, the big winter cold snap that has been gripping much of the United States since December is nearing its end. Temperatures in most places from the Plains to the East Coast have started to rebound and no renewed surges of Arctic air are on the horizon after a final weak front moves through the East Tuesday. But the damage is done in places from the Dakotas and Montana to Florida: burst pipes, roads that drifted shut, and wind chills lower than -50 in the North, and car crashes on icy roads, power outages, and record cold that has chilled the South.

The jet stream pattern for the last two weeks comprises a deep trough over eastern North America that allowed Arctic air to pour into the United States east of the Rockies. (Credit: Chicago NWS Forecast Office)

Last Thursday, the wind chill in Bowbells, North Dakota hit 52° F below zero. That degree of cold “freezes your nostrils, your eyes water, and your chest burns from breathing — and that’s just going from the house to your vehicle,” said Jane Tetrault of Burke County. Her vehicle started, but the tires were frozen. “It was bump, bump, bump all the way to work with the flat spots on my tires,” she said, adding, “It was a pretty rough ride.”
Snow and icy winds whipped southward from the Midwest into Tennessee, Georgia, and Alabama late in the week, making travel a disaster in Memphis and Atlanta. Video of cars sliding off roads or into each other played every half hour on The Weather Channel into the weekend.
Even the Sunshine State had wintry precipitation with this unusual cold surge—something not seen in more than 30 years. The weekend into Monday was especially brutal by Florida standards. With temperatures in the 30s and low 40s, light rain enveloped the peninsula Friday night through Saturday. Sleet fell in spots from Jacksonville and Ocala southward through Orlando, Tampa, and Melbourne into Palm Beach. A few wet snowflakes mixed in here and there with snow reported by trained spotters as far south as Kendall, a southern suburb of Miami. In some places north of Tampa, enough sleet accumulated on cars and outdoor furniture to build little “sleet” men, complete with tiny hats and tree-twig arms, their photos rivaling those taken of snowmen built in Tampa on January 17, 1977. (View a photo of Florida sleet from a snow and ice slideshow on Tampa’s baynews9.com.)
Clearing led to record morning lows both Sunday and Monday that threatened harm to Florida’s $3 billion citrus industry. Temperatures bottomed out at 25° in Tampa, 29° in Orlando, and 31° in Ft. Myers. On Sunday, the temperature in Miami tied the 1970 record for the date with 35°, and a 36° low Monday morning broke the previous record for the date of 37° set in 1927. Despite the records, it has been the duration of the cold, especially in the South, that makes this cold snap memorable. Morning after morning since the previous weekend, photos of Florida strawberries encased in ice showed up on newscasts. Such protective measures against the frigid temperatures are expected for several more mornings in central Florida, even as the chill slowly moderates.
The cold was even long-lasting in the Midwest and Plains, as noted in TWC meteorologist Tim Ballisty’s article “It’s Cold But So What?” last week. He points out that Chicago hasn’t been above freezing since Christmas Day, at the time 11 straight days and counting. Cleveland had 10 consecutive days of snow, and that count continued right into the weekend.
Unlike the extensive heat waves of recent summers, this long and harsh cold snap resulted in relatively few new temperature records. At the Annual Meeting in Atlanta, Gerry Meehl of NCAR will explore the rising ratio of record high temperatures to record low temperatures, which is expected to markedly increase by the middle of the century with current projections of climate warming.

Innovations in Climate Adaptation

UPDATE, 1/17/10: Due to a last-minute scheduling change, Amanda Lynch will be unable to attend the Annual Meeting. Adaptive Governance and Climate Change will still be a featured release at the AMS Book Launch Party on Monday.
The recent Copenhagen conference provided yet more evidence that countries with completely different priorities are often reluctant to enter into complex and costly agreements with each other. While international negotiations may seem cumbersome at best,  some scholars argue that climate change may best be solved at the local–rather than international–level. Local action may not only be more effective but also could also someday might lead to international agreements.
This local-first policy approach will be explored in a variety of ways at the AMS Annual Meeting, headlined by the release of a new AMS book, Adaptive Governance and Climate Change, by Ronald Brunner and Amanda Lynch. Brunner and Lynch show how locally based programs foster the necessary diversity and innovation for climate adaptation. Adaptive Governance and Climate Change Their book focuses on the real-life climate  issues faced by Barrow, Alaska—and analyzes how the policies developed to address those issues could be adopted by other communities.
In Atlanta, Lynch will be available to discuss these policy perspectives when the book is released as part of the AMS Book Launch Party (Monday, 5:30 p.m., exhibit hall B1, booth 146). In addition, she will be signing copies of the book on Monday and Wednesday (2:45–4:00 p.m., exhibit hall B2).
Communities across the world are moving toward adaptive governance, as can be seen in a number of presentations at the Annual Meeting. Nanteza Jamiat’s poster on “Adaptation Challenges to Climate Change Disasters in the Karamoja Cluster (Cattle Corridor) in Uganda” (at the student poster session, Sunday, 5:30–7:00 p.m., exhibit hall B2) addresses the interrelationship of climate change and agriculture in a country where both are a way of life for most of the population. Barry Smit’s presentation on “Traditional Knowledge and Adaptation to Climate Change in the Canadian Arctic” (Wednesday, 9:00–9:15 a.m, B213) focuses on indigenous people in the Arctic and the cultural barriers that sometimes need to be broken in order to implement local adaptation initiatives. The Pacific Island nation of Tuvalu is the subject of “Weathering the Waves: Climate Change, Politics, and Vulnerability in Tuvalu,” a poster by Heather Lazrus (Monday, 2:30–4:00 p.m., exhibit hall B2) that shows how one of the most vulnerable areas in the world is in some cases reverting to traditional governmental methods to meet the perils of climate change. And Cynthia Fowler’s presentation on “Coping in Kodi: Local Knowledge about and Responses to Climate Change and Variable Weather on Sumba (Eastern Indonesia)” (Tuesday, 4:15-4:30 p.m., B213) notes that many people in Indonesia’s marginal environments  relate climate change to local development, thus crystallizing in one small area many of the problems that were evident at Copenhagen between developing and developed countries.

Charting the Course of Arctic Warmth…and Oceanography

While many parts of the country have recently been experiencing conditions that residents might call “Arctic,” the Arctic region itself has been warming since at least the early 1990s, reaching warmth unprecedented in the last century. The consequences for global climate are potentially critical―particularly if fresh water from melting ice and increased atmospheric precipitation in the Arctic slow the overturning circulation of the North Atlantic. With Arctic sea ice melting dramatically in recent years, scientists  are trying to understand the influence of the warmer water that flows into the Arctic from the North Atlantic.
At the National Oceanography Centre (NOCS) in Southampton, United Kingdom, scientists using high-resolution computer models found that from 1989 to 2009, about 50% of the salty North Atlantic water entering the Arctic Ocean came through Fram Strait, a deep channel between Greenland and the Norwegian island of Spitsbergen that connects the Nordic Seas to the Arctic Ocean. The Barents Sea contributes about as much Atlantic water to the Arctic, but the Fram Strait water carried most of the heat that has been a primary cause of Arctic ice melting.
An example of the modeling in this study, published in the January 2010 issue of Journal of Marine Systems, can be seen in the image below, which shows a computer simulation of ocean temperatures at a depth of 100 meters and sea ice thickness in September 2006. The pathways of warm saline water toward the Arctic have previously been poorly understood, but here the 8-km resolution defines three distinct pathways for this water to move under the more pure Arctic water, thus pumping heat northward between 50 and 170 meters below the surface.
“Computers are now powerful enough to run multidecadal global simulations at high resolution,” said NOCS scientist Yevgeny Aksenov. “This helps to understand how the ocean is changing and to plan observational programs so as to make measurements at sea more efficient.”
Ocean-climate interactions are a primary focus of the ocean science research priorities recommended by the U.S. National Science and Technology Council’s Joint Subcommittee on Ocean Science and Technology (JSOST) in their 2007 report, “Charting the Course for Ocean Science in the United States for the Next Decade: An Ocean Research Priorities Plan and Implementation Strategy.” As our understanding continues to evolve regarding the ocean and its influence on the Earth system, the priorities outlined in this report have also evolved. A town hall meeting on “Refreshing Our Ocean Research Priorities” (Monday, 12:15–1:15 p.m., B212) at the upcoming AMS Annual Meeting will explore some of these developments and give participants a forum to discuss topics of interest with the chairs of JSOST.

arctic_sea_update