16-20 April 2018

ITEMS OF INTEREST

• Sunrise is getting earlier "Way Up North" -- The station technician at NOAA's Barrow Atmospheric Observatory in northern Alaska recently provided a photograph using a drone of sunrise above the flat headland jutting out into the Arctic Ocean. The Barrow Atmospheric Observatory, which is located at 71 degrees North latitude, is one of NOAA’s stations for monitoring long-term changes in the global atmosphere. With the passage of the vernal equinox late last month, sunrises occur earlier in the day at a rapid pace, while sunsets are getting later. As of the first week of April, Barrow is gaining approximately 10 minutes of sunlight each day. [NOAA Feature Photo]
• Free admission into the National Parks and Monuments-- In observance of National Park Week (21-29 April 2018), the National Park Service will waive entrance fees this coming Saturday (21 April). This fee waiver will cover entrance and commercial tour fees in many of the national parks and monuments administered by the Park Service. [National Park Service Fee Free Days]
• Celebrate Earth Day --This Sunday (22 April 2018) marks the 49th Earth Day, first proposed by the late Senator Gaylord Nelson of Wisconsin in 1970 as a teach-in to heighten awareness of the environment. The Nelson Institute for Environmental Studies at the University of Wisconsin-Madison has posted a website called "Gaylord Nelson and Earth Day: The Making of the Modern Environmental Movement" that highlights Senator Nelson and his idea became Earth Day. Several governmental websites provides links to various activities and resources planned for this week, including a website maintained by the US Environmental Protection Agency (EPA).
  NASA has produced a high resolution printable Earth Day poster for 2018 that features an artistic illustration of a solar eclipse around Earth. This year's poster can be downloaded as a pdf file along with a collection of illustrated posters in NASA's annual celebration of Earth Day. High resolution printable PDF files are available for each Earth Day since 2010. [NASA Science Toolkits]
• Watching the seasons -- phenology observations and climate change -- For centuries, interested citizens and scientists have been recording the dates of recurring biological and other natural events that appear to be related to the seasons. This tracking of these natural cyclic events, called phenology, if extended over many years, can be used to document how long-term changes in these seasonal events change in response to long-term changes in climate. For more information on recent efforts to establish a nationwide phenological observation network and how it could be used for studying climate change, see this week's Supplemental Information...In Greater Depth.

CURRENT CLIMATE STATUS

• March 2018 weather and climate for the nation reviewed -- Scientists at the NOAA National Centers for Environmental Information (NCEI) recently reported on their analysis of preliminary weather data collected during the month of March 2018. When averaged across the contiguous United States, the monthly temperature for March 2018 was 42.6 degrees Fahrenheit, which was 1.1 Fahrenheit degrees above the 20th-century (1901-2000) average. Therefore, this past month was the 49th warmest March since a comprehensive climate network began in 1895. Eight states along the Atlantic Seaboard, running from Pennsylvania southward to Florida, had below-average statewide temperatures for March that rank within the lowest third on record for their respective states. Conversely, nine states across the southern Plains, the southern and central Rockies, and the Southwest had statewide average temperatures that were in the top third of the record. Maine also experienced an above-average March temperature. The remainder of the 48 contiguous states in the West and across the northern Plains and Mississippi Valley had near-average statewide temperatures in March.
  The average maximum (or daytime) temperature for this past March across the "lower 48" was the 55th highest on record, while the average minimum (or nighttime) temperature was the 41th highest. Virginia reported its eleventh lowest maximum monthly temperature on record.
  Alaska reported its ninth warmest March in their 94-year period of record, with a monthly average temperature that was 6.9 Fahrenheit degrees above the long-term average.
  The average precipitation across the contiguous U.S. for March 2018 was 2.42 inches, which was 0.09 inches below the 20th-century average, making the month the 55th driest March since 1895. Sixteen states scattered across the Southeast, New England, the Great Lakes and the Four Corners region of the Southwest reported below-average precipitation. On the other hand, seven states scattered primarily across the West and the Dakotas had statewide precipitation totals that were above the long-term average. North Dakota reported a statewide March precipitation total that was eleventh highest in the 124-year record. The remaining two dozen states that comprise the "Lower 48" had statewide precipitation levels that were close to average.
  Data analyzed by the Rutgers Global Snow Lab indicate the March snow cover extent across the contiguous US was the sixth highest areal extent for the 52-year period of record across the 48 contiguous states, as well as being the largest March snow cover extent since 1979. Above-average snow cover was reported across the northern tier of states, running from the Northwest eastward across the northern Rockies, the northern Plains to the Midwest and in the Northeast. On the other hand, below-average snow cover was found across the southern Rockies, the central Plains and the Great Lakes. [State of the Climate NOAA/NCEI]
  NOTE: A description is provided of the climatological rankings employed by NCEI for their monthly and seasonal maps. [NOAA/NCEI]
  The Chief of the Climate Monitoring Branch at NCEI, Deke Arndt, posted a "Beyond the Data" blog in which he discusses this past "cold season", the six months running from Oxctober 2017 through March 2018 in context with the temperature trends across the nation over the last 50 seasons. The cold-season average temperature has increased by 6.3-Fahrenheit degrees per century across the contiguous U.S. (CONUS), which is more than the 5.2-Fahrenheit degrees per century rise in annual average temperatures for CONUS. The Southwest has been experiencing warmer cold-seasons, with the average October-March temperatures in Arizona increasing by 7.0-Fahrenheit degrees per century over the last 50 years. However, this increase pales in comparison with the 17.1-Fahrenheit degree per century increase across Alaska's North Slope. Deke also discusses the addition of three weather/climate-related disasters to the Billion Dollar Disaster list recently released by NCEI (see item below). [NOAA Climate.gov News]
• March national drought report -- The National Centers for Environmental Information has posted its March 2018 drought report online. Using the Palmer Drought Severity Index, approximately eleven percent of the contiguous United States experienced severe to extreme drought conditions at the end of March, while approximately six percent of the nation had severely to extremely wet conditions at that time.
• Nation experiences three billion-dollar disasters attributed to weather and climate during first quarter of 2018 -- NOAA’s NCEI recently reported that during the first three months of 2018, the United States experienced three weather and climate disasters, each resulting in losses that exceeded $1 billion. One of these was a severe thunderstorm outbreak in mid-March (18th-21st) across the mid-South and Southeast, accompanied by tornadoes, strong winds and hail. Over 20 tornadoes were reported in Alabama. Total damages exceeded $1 billion and at least three people died. The other two billion-dollar disasters were two winter storms in the eastern U.S, with one Nor'easter occurring along the Eastern Seaboard from the Carolinas to Maine in early January (3rd-5th) that resulted in 22 fatalities, while the other Nor'easter hitting the Middle Atlantic and New England States during the first three days in March, resulting in nine fatalities. [NOAA News]
  The NCEI list of billion disaster events in the U.S. beginning in 1980 and running through early April 2018 is available.
• Northern California gets another soaking from an atmospheric river in early April -- A meteorologist with NOAA’s Climate Prediction Center wrote a feature for the ClimateWatch Magazine describing another atmospheric river that gave sections of northern California torrential rains during the first week of April. These rains caused local flooding and some melting of the snowpack in the high country of the Sierras. The atmospheric river represents a plume of water vapor, clouds and precipitation that is typically carried long distances from the oceanic areas of tropical and subtropical latitudes to midlatitude landmasses, where abundant precipitation can be produced. An image was generated showing the forecast of precipitable water for a day in early April, with the plume directed at northern California. Precipitable water is a measure of the water vapor in a vertical column in the atmosphere, expressed as the depth of the water that would condensed from this water vapor. [NOAA Clim.gov News]
• New online "snow drought" page is launched -- NOAA's National Integrated Drought Information System (NIDIS) recently unveiled a "snow drought" web page that provides data, maps and other resources to those who are concerned with the ongoing snow drought across the West. A snow drought represents a time interval with abnormally low snowpack for the time of year, caused either by below-normal cold-season precipitation (dry snow drought) or a lack of snow accumulation, despite near-normal precipitation (warm snow drought). This new webpage is the result of a multi-agency collaborative effort designed to increase awareness of snow drought and provide data and necessary tools to decision makers and resource managers. [U.S, Drought Portal News]

CLIMATE FORCING

• Major North Atlantic circulation system is weakening with changes in redistribution of ocean heat -- Direct oceanographic measurements have found that the Atlantic Meridional Overturning Circulation (AMOC), a large-scale system of ocean currents in the Atlantic Ocean, has been slowing over the last several decades. A team of researchers from Europe and the U.S. report that their computer model simulations appear to confirm these observations that show the AMOC has slowed or weakened by about 15 percent since the 1950s. One of NOAA's global climate model was used to identify the characteristic sea surface temperature patterns. The slowing of AMOC, attributed to a changing climate associated with rising atmospheric carbon dioxide levels, has caused the redistribution of heat in the North Atlantic Ocean. The resulting changes have been felt along the Northeast U.S. Shelf and in the Gulf of Maine, which has warmed 99 percent faster than the global ocean over the past ten years. These changes are impacting distributions of fish and other species and their prey. [NOAA Fisheries Northeast Fisheries Science Center News]

CLIMATE FORECASTS

• Updated El Niño/Southern Oscillation (ENSO) Diagnostic Discussion is released -- Late last week forecasters at NOAA's Climate Prediction Center (CPC) and the International Research Institute for Climate and Society (IRI) released their monthly El Niño/Southern Oscillation (ENSO) Diagnostic Discussion. They reported that La Niña conditions continued to weaken through March 2018 as below-average sea surface temperatures (SSTs) were reported across the east-central and eastern equatorial Pacific Ocean, but a warming was detected of the ocean waters below the surface. Atmospheric conditions across the tropical latitudes of the Pacific basin were also suggestive of a weak La Niña. Many of the prediction models used by the forecasters indicate further decay of the La Niña and a transition to ENSO-neutral conditions by the end of May, with neither La Niña nor La Niña conditions prevailing. The forecasters consider this transition from La Niña conditions to be likely, with a 50 percent chance of occurring. The ENSO-neutral conditions were expected to remain through Northern Hemisphere summer. Therefore, the CPC's ENSO Alert System Status still maintains a La Niña advisory since the La Niña conditions were still being detected. [NOAA Climate Prediction Center]
  An ENSO blog was written by a contractor with CPC describing the weak La Niña conditions that remained across the equatorial Pacific, describing how the SST anomalies (differences between observed and long-term temperatures) across the eastern Pacific remained close to the threshold that would be considered a La Niña. Subsurface temperature anomalies in the Pacific Ocean along the Equator were described. In addition, the atmospheric conditions involving convection, outgoing long-wave radiation and winds were also considered. [NOAA Climate.gov News]
• An El Niño forecast from Down Under -- Forecasters with the Australian Bureau of Meteorology recently reported that ENSO-neutral conditions were currently occurring in the region near Australia. They foresaw these conditions would continue for the next six months. Therefore, the Bureau's ENSO Outlook status remains as ENSO-Inactive. [Australian Government Bureau of Meteorology]

CLIMATE AND THE BIOSPHERE

• West Coast ecosystems may be destabilized by extreme climate variability -- A team of researchers have found that extreme climate variability over the last century across western North America may be destabilizing both marine and terrestrial ecosystems. They claim that climate is increasing its control of synchronous ecosystem behavior in which species populations rise and fall together. This increase in the synchrony could expose marine and terrestrial organisms to higher extinction risks. [Oregon State University News]

CLIMATE AND SOCIETY

• Nation’s businesses and economy are helped by weather data services -- A report was recently released that examines user engagement with the climate and weather data that are archived b' NOAA’s National Centers for Environmental Information (NCEI). The value that the free and publicly available provision o' NCEI’s information to the weather service provider industry, which then creates value-added products and services to serve a range of sectors. Interviews were conducted with key sector stakeholders' NCEI’s information provides an important resource to more than 250 weather service providers that contribute $7 billion annually to the U.S. economy. [NOAA NCEI News]
• Earthweek -- Diary of the Planet [earthweek.com]

Concept of the Week: Human health and climate change

Climate scientists and other experts studying the projected changes in the global climate have been concerned that these changes can have potentially adverse effects upon human health. The specific health outcomes are highly uncertain. However, according to the U.S. Global Change Research Program's (USGCRP) Global Climate Change Impacts in the United States Report, several key health-related issues on the national level that could be affected by climate are: heat issues and heat waves, air quality, extreme weather events, heat associated diseases, pollen effects, and vulnerable groups.

One of the more obvious consequences of changes in climate is the increased incidence of temperature-related illnesses and deaths, especially those that would occur with heat waves, or episodes of extreme heat. Projected increases in air temperature and rising humidity levels across the nation during the 21st century would also be accompanied by increased frequency and intensity of heat waves, where air temperature and heat indices would exceed certain threshold levels for several days. In the United States, recent heat waves have resulted in numerous deaths, especially in large metropolitan areas. The elderly, the poor in urban areas and those with underlying health issues (such as diabetes and hypertension) appear to be the most susceptible to higher air temperatures and extended heat waves. Some models indicate that mortality rates would increase more rapidly in northern cities, where populations are less accustomed to the less-frequent heat waves. Using a model that includes a high emissions scenario, the average annual number of heat-related deaths in the Chicago (IL) metropolitan area could reach 700 by 2050 and 1200 by 2100.

Certain health effects would be related to extreme weather events. In addition to above-described heat waves, increases in injuries and deaths could occur if extreme weather events such as tropical cyclones (hurricanes or tropical storms) and floods would increase in frequency. The disaster wrought by Hurricane Katrina on New Orleans, LA and the Gulf Coast in 2005 could serve as an example. Water-borne diseases can be related to water contamination caused by heavy precipitation events. A Cryptosporidium outbreak in Milwaukee, WI occurred in 1993 in which 54 people died when the municipal drinking water supply became contaminated by sewage that was not properly treated because of overtaxed storm sewers. Some climate models suggest an increased incidence of extreme weather events across the nation during a warmer 21st century, especially in the frequency of excessive precipitation events. If improvement in the sewerage and water treatment facilities are not made, projected in creases in intense precipitation events could pose an increased health risk to many people, especially in the Northeast and Midwest. Chicago could have sewer overflow events going up by 50 to 120 percent in the future. In addition to the casualties that would be directly related to the natural disasters, such as drowning, some secondary effects to these disasters have been suggested, including problems with public health infrastructures and with post traumatic stress disorder following the event.

Increases in those infectious diseases borne by insects, ticks and rodents could be possible with future changes in climate. Temperature appears to serve as a major constraint on the range of microbes and vectors, meaning that some diseases could be spread poleward with higher temperatures. While malaria, yellow fever and dengue fever have been nearly eradicated across the nation, some other diseases, such as Lyme disease and encephalitis, transmitted between humans by blood-feeding insects, ticks and mites, may occur in some areas as the result of extended spells of warm wet winters, cold springs. Rising temperatures and carbon dioxide concentrations appear to increase pollen production and lengthen the pollen season. Consequently, highly allergenic pollen could pose an increased health risk to many people.

The report also cautions that particular groups of people could be especially vulnerable to future climate change, highlighting the increases in the incidence of diabetes and obesity, which make individuals more susceptible to disease or air quality or heat.

Historical Events:

• 16 April 1975...A single storm brought 119 inches of snow to Crater Lake, OR, establishing a state record. (Intellicast)
• 16 April 2007...An intense nor'easter raging along the New England Coast caused the barometric pressure reading at Albany, NY to fall to 28.84 inches of mercury (976.68 mb), the lowest barometric pressure reading ever recorded in April in the Empire State's capital city. (The Weather Doctor)
• 17 April 1948...A ten-minute deluge dumped 34 mm (1.34 inches) of rain on Tauranga, the wettest 10 minutes ever recorded on New Zealand. (The Weather Doctor)
• 17 April 1997...The Red River of the North crested at Fargo, ND, with a record crest of 39.6 ft, which is 22.6 ft above flood stage. This record flood, produced by several major winter storms, heavy spring rain, rapid snow melt, and ice jams, was responsible for at least 11 deaths (7 in North Dakota and 4 in Minnesota) and tremendous property damage along with large scale evacuations of residents from the Grand Forks metropolitan area. Dikes along the river gave way. Overall damage and cleanup costs have been estimated to range from $1 to $2 billion in Grand Forks, where a portion of the downtown burned as firefighters had a difficult time reaching the buildings due to the flood. [NOAA/NCDC]
  Editor's Note: "History repeats!" During the second week of April 2001, the Red River at Grand Forks reached a river stage of 45 ft, or approximately 17 ft above flood stage and about 7 ft below the top of the levee. In 1997 this gauge measured a record 54.35 ft. EJH
• 17 April 2004...A 182-day long streak of no measurable rain began in San Diego, CA. The streak ended on 17 October 2004. (National Weather Service files)
• 18 April 2004...A record 182 consecutive days of no measurable precipitation began in San Diego, CA on this date, which ended on 17 October 2004 with 0.09 inches of rain. This new record broke the 181-day record set the previous year. Interestingly, the rain that followed the more recent dry spell resulted in October 2004 becoming San Diego's wettest month on record (4.98 inches). (Accord Weather Guide Calendar)
• 19 April 1973...Glenrock, WY received 41 inches of snow in just 24 hours, and a storm total of 58 inches, to establish two state records. (18th-20th) (David Ludlum) (The Weather Channel)
• 20 April 1880...Sacramento, CA had its heaviest 24-hour rainfall when 7.24 inches fell. (Intellicast)
• 20 April 1901...A spring storm produced unusually heavy snow in northeast Ohio. Warren received 35.5 inches in thirty-six hours, and 28 inches fell at Green Hill. Akron established April records of 15.6 inches in 24 hours, and 26.6 inches for the month. Pittsburgh, PA established April records of 12.7 inches in 24 hours, and 13.5 inches for the month. (David Ludlum) (The Weather Channel)
• 20 April 1984...A temperature of 106 degrees in Del Rio, TX set a new record high for April. (Intellicast)
• 20 April 1987...Fifty-two cities in the central and eastern U.S. reported new record high temperatures for the date. The high of 92 degrees at Memphis, TN was a record for April, and the high of 94 degrees at Little Rock, AR equaled their April record. (The National Weather Summary)
• 20 April 1989...Hot weather spread from the southwestern U.S. into the Great Plains Region. Twenty-three cities reported new record high temperatures for the date. The afternoon high of 104 degrees at Tucson, AZ was an April record, and highs of 87 degrees at Provo, UT, 90 at Pueblo, CO, and 85 at Salt Lake City, UT, equaled April records. (The National Weather Summary)
• 21 April 1989...The temperature at Las Animas, CO soared to 100 degrees to establish a state record for April. Twenty-two cities in the central and southwestern U.S. reported record high temperatures for the date. Eight cities equaled or exceeded previous April records. Tucson, AZ experienced its fourth consecutive day of record heat with an afternoon high of 104 degrees, bringing the total number of days during the month of April 1989 to 11 when record high values had either been matched or broken. (The Weather Channel) (The National Weather Summary) (Intellicast)
• 21 April 1992...Two inches of snow fell at International Falls, MN, bringing the winter season snowfall to 106.7 inches and setting a new all-time record for the city. The old record was 104.7 inches set back in the 1988-89 winter season. (Intellicast) Editor's Note: The seasonal snowfall accumulation for the 2008-09 winter reached a record 125.6 inches. EJH
• 22 April 2003...Tropical Storm Ana formed in the southwestern North Atlantic Ocean, becoming the first Atlantic tropical storm (since records began in 1871) to form during the month April. Maximum sustained winds reached 50 mph. (The Weather Doctor)

Return to ECS RealTime Climate Portal

Prepared by Edward J. Hopkins, Ph.D., email hopkins@aos.wisc.edu
© Copyright, 2018, The American Meteorological Society.