WEEKLY WEATHER AND CLIMATE NEWS

23-27 April 2018

Items of Interest:

• Becoming AWARE -- During this coming week of 23-27 April 2018, Pennsylvania and South Dakota will conduct Severe Weather Awareness Week in their respective states. These weeks are usually scheduled before the onset of the severe weather season in that particular state. If you live in any of these states, you should take time to become familiar with the various public affairs announcements issued by your local National Weather Service Office.
• Celebrating National Arbor Day -- This coming Friday, 27 April 2018, many locations across the nation will celebrate Arbor Day, a day when the planting of trees is encouraged. Arbor Day was originally proposed in 1872 by J. Sterling Morton, Nebraska's first newspaper editor, and continues to be most often celebrated by individual states on the last Friday in April. However, since planting conditions vary greatly due to the state's climate it may occur from September to May. In Arkansas, Arbor Day is celebrated on the third Monday in March, but in Alaska, the date is the third Monday in May. For your state's observance (and name of the official state tree), please consult the National Arbor Day Foundation.
• National Science Bowl set for next weekend -- The US Department of Energy (DOE) National Science Bowl®, a nationwide academic competition for middle and high school students will be held through next weekend (26- 30 April 2018) in Washington, DC. This event will test students' knowledge in all areas of science and is meant to encourage high school students to excel in science and math and to pursue careers in those fields. [DOE Office of Science]

Weather and Climate News Items:

• Eye on the tropics -- No tropical cyclones were detected across any ocean basin during the last week.
• The 2017 hurricane season reviewed -- The 2017 hurricane season in the North Atlantic along with the eastern and central North Pacific is reviewed and compared to the more than 150 years of record keeping in the North Atlantic and the 40 years in the eastern North Pacific. [AMS DataStreme Atmosphere]
• Hurricane awareness tour commences to Mexico and the Caribbean -- NOAA and US Air Force Reserve hurricane experts will embark at the start of this week (23-28 April 2018) on a six-day, five-city tour to Mexico, Panama, Jamaica and Puerto Rico in a "hurricane hunter" aircraft designed to raise public hurricane awareness in communities in several countries surrounding the Caribbean Sea. A series of events will be hosted that would include tours aboard the Air Force Hurricane Hunter aircraft and a high-altitude research jet that NOAA uses. [NOAA Media Release]
• Latest snow of season histories are available for several thousand U.S. weather stations -- With many areas of the nation experiencing late-season snow during the first three weeks of April, interest has raised in finding the latest date of the last measurable snow of the season at a close weather station. (Measurable snow is defined as a snowfall accumulation of 0.1 inches or greater.) NOAA's National Centers for Environmental Information has assembled an interactive map that allows the user to obtain the dates of the last measurable snowfall for several thousand weather stations across the contiguous United States in the Global Historical Climatology Network that have at least 20 years of record. Clicking on a station location will provide not only the date of the latest observed snowfall at that location, but the amount of this last snow and the first year of observation for that station. [NOAA Climate.gov News] (For completeness, a corresponding interactive map has been produced last autumn from the Global Historical Climatology Network that provides the date of occurrence of the first measurable snow of the snow season.)
• Exceptional drought conditions expand across several states in the Southwest -- An animated sequence of maps depicting drought conditions across the contiguous United States beginning in mid-January 2018 and ending at the start of last week shows the relatively rapid expansion of "exceptional drought" conditions across a large swath of the Southwest, running from the Panhandles of Texas and Oklahoma westward to the Four Corners area (where Arizona, Colorado, New Mexico and Utah meet). "Exceptional drought", the most intense level of drought according to the National Drought Monitor, is responsible for widespread crop/pasture losses; shortages of water in reservoirs, streams, and wells, which create water emergencies. The animation showed that "extreme drought" (the next lower drought classification level) was found across sections of Oklahoma in mid-January, but during subsequent months, the region of extreme drought expanded westward, with a region of exceptional drought appearing across the Oklahoma and Texas Panhandles in March and April, to include sections of seven states. [NOAA Climate.gov News]
• Viewing "spider lightning" from new lightning mapper on GOES-East satellite -- Several animations of images were obtained last October from the Geostationary Lightning Mapper (GLM) onboard NOAA's GOES-16 (now GOES-East) satellite showing what is referred to as "spider lightning" racing across the layer of stratiform clouds moving across the nation's midsection behind a convective line of thunderstorms. Spider lightning refers to long, horizontally traveling flashes often seen on the underside of stratiform clouds. [NOAA NESDIS News]
• Review of global weather and climate for March 2018 -- Using preliminary data collected from the global network of surface weather stations, scientists at NOAA's National Centers for Environmental Information (NCEI) have determined that the combined global land and ocean surface temperature for March 2018 was the fifth highest for any March since sufficiently detailed global climate records began in 1880. This global temperature for March 2018 was 1.49 Fahrenheit degrees above the 20th century (1901-2000) average.
  When considered separately, the average land temperature for March 2018 was the seventh highest land temperature for any March in the 139-year period of record. Last month's average temperature over the oceans was the fifth highest for any March. Interestingly, the March 2018 monthly global combined sea-land temperature departure from the 20th century average represents the smallest March temperature departure from average since 2014.
  The researchers at the National Snow and Ice Data Center noted the areal extent of the Arctic sea ice for March 2018 was the second smallest since satellite surveillance began in 1979. In addition, the extent of the Antarctic sea ice was the seventh smallest in the 39-season record. According to data from the Rutgers Global Snow Lab, the Northern Hemisphere snow cover extent for March was the 13th largest in the 52-year period of record of satellite observations. [NOAA/NCEI State of the Climate] A global map of Selected Significant Climate Anomalies and Events for March 2018 is available from NCEI.
  A summary article describing the global climate for March and the year to date is available. [NOAA News]
• New Seasonal Climate Outlooks released -- During the last week, forecasters at NOAA's Climate Prediction Center (CPC) released their Three-Month (Seasonal) Climate Outlooks for the three-months running from May through July 2018, which contains the last month of meteorological spring and the first two months of two months of meteorological summer. Specific details of their outlooks include:
• Temperature and precipitation outlooks -- According to their temperature outlook, approximately 80 percent of the 48 contiguous United States should experience a high chance of above average temperatures for these three upcoming months, with the greatest probability of such an occurrence being found across sections of the Southwest (Arizona and New Mexico) and in New England and adjacent section of New York State. Only sections of the northern Rockies, the northern Plains and the Upper Midwest were expected to have nearly equal chances of warmer or cooler than normal conditions.
  Their precipitation outlook calls for better than even chances of dry conditions for May through July 2018 across the northwestern quadrant of the "Lower 48", with the highest probability of dry conditions centered upon Oregon and adjacent sections of neighboring states. Conversely, the northeastern quadrant of the nation was expected to have a better than even chance of having above median precipitation. These regions that could have above average precipitation stretched from the western Great Lakes eastward to Maine and southward to North Carolina. The rest of the contiguous United States should have equal chances of below and above median precipitation for late spring and early summer. [NOAA Climate Prediction Center] Outlooks for May are also available. A summary of the prognostic discussion of the outlook for non-technical users is available from CPC. These forecasts were based in part upon the anticipated transition from a weak La Niña to ENSO-neutral conditions during late meteorological spring (May) and into early summer 2018 in the Northern Hemisphere.
• Seasonal Drought Outlook released -- The forecasters at CPC also released their US Seasonal Drought Outlook that would run from mid-April through July 2018 in which drought conditions were expected to persist across the West, primarily in the 4 Corners (Arizona, Colorado, New Mexico and Utah) and southern California, where moderate to exceptional drought conditions were currently occurring. Drought was expected to continue also across the southern Texas, the lower Missouri Valley and in Oregon, where some expansion of the drought area was anticipated. The Dakotas along with region across the Southern Rockies and the adjacent Plains currently under moderate to exceptional drought should also expected to see continued drought conditions into midsummer. Improvement in drought conditions was expected across the scattered areas Southeast. Some of these areas could be removed from drought consideration. Note: a Seasonal Drought Outlook Discussion is included describing the forecasters' confidence.
• Record low winter sea ice in Alaska's Bering Strait creates problems for coastal communities -- During the last week, the International Arctic Research Center at the University of Alaska Fairbanks produced a four-page summary of the winter 2018 sea ice conditions in and around the Bering Strait off Alaska's western coast. The amount of sea ice in the Bering Sea was the lowest since 1850, the result of unusual winter conditions that have prevailed in the region, involving above average air and water temperatures and more frequent storms with an increased frequency of winds from the south. The lack of persistent sea ice this winter caused a variety of problems for coastal communities. [NOAA Climate.gov News] or [University of Alaska Fairbanks International Arctic Research Center]
• National wind turbine database and associated map viewer are released to the public -- During the last week, the U.S. Geological Survey (USGS) and the U.S. Department of Energy (DOE) announced the release of the United States Wind Turbine Database (USWTDB) and the USWTDB Viewer designed to access this new public dataset on maps showing location of existing wind turbines. The USWTDB, which was developed in partnership with DOE's Lawrence Berkeley National Laboratory and the American Wind Energy Association, is a comprehensive dataset of U.S. wind turbine locations and characteristics that can be easily accessed online using the accompanying viewer. [USGS News]
• Improved weather and climate services could boost food security -- The World Meteorological Organization's (WMO) Commission for Agricultural Meteorology met last week for its quadrennial session in Incheon, Republic of Korea. The focus of the session was on improved weather and climate services for farmers and the agricultural sector in order to boost food security and sustainable development. Discussion was made on how to balance the need to provide food for a growing global population with minimizing the impact of climate change on agriculture and reducing greenhouse emissions from agriculture. [World Meteorological Organization News]
• New instrumentation being developed to increase views of ocean-atmosphere interactions -- Scientists at NASA's Jet Propulsion Laboratory have been developing a new Earth science radar instrument called DopplerScatt, a spinning radar unit that "pings" the ocean's surface, allowing it to take measurements from multiple directions at once. Flying onboard an aircraft, DopplerScatt will provide a new capability to measure both winds and currents simultaneously. [NASA Armstrong Flight Research Center Feature]
• Greenhouse gas research campaign resumes across eastern U.S. -- Atmospheric Carbon and Transport-America (ACT-America), a five-year NASA airborne campaign designed to study the transport and fluxes of atmospheric carbon dioxide and methane, has begun its fourth campaign earlier this month. This year's six-week campaign commenced during the second week of April as flights were conducted from Shreveport, LA. During this week, the mission's base of operations has transferred to Lincoln, NE, where it will continue through the first week of May, when it will then return to the Langley Research Center in Virginia. The intent of ACT-America has been to investigate relationships between atmospheric carbon dioxide and methane concentrations and weather systems in the eastern half of the U.S. More accurate and precise estimates of the sources and sinks of these gases are needed for climate management and for prediction of future climate. [NASA Langley Research Center Feature]
• Grassland plants react unexpectedly to increased carbon dioxide levels -- Researchers at the University of Minnesota-Twin Cities and colleagues from the University of Wisconsin-Eau Claire and Australia's Western Sydney University recently reported on their twenty-year study involving exposing two different types of grasses to different levels of carbon dioxide (CO₂). Warm-season C₄ grasses and cool-season C₃ grasses were used in the study, and the CO₂ levels were increased from the current atmospheric levels to levels anticipated by the end of this century. For the first 12 years, researchers found what they expected regarding how different types of grasses reacted to CO₂ changes, notably C₃ grasses would grow more under elevated CO₂, while C₄ grasses would not be affected by higher CO₂ levels. However, they found an unanticipated turn during the study's last eight years, where the C₄ plant species grew more in an elevated CO2 environment than C₃ plants. [University of Minnesota-Twin Cities News]
• An All-Hazards Monitor -- This Web portal provides the user information from NOAA's National Weather Service, FAA and FEMA on current environmental events that may pose as hazards such as tropical weather, fire weather, marine weather, severe weather, drought and floods. [NOAA/NWS Daily Briefing]
• Earthweek -- Diary of the Planet [earthweek.com]