WEEKLY CLIMATE NEWS

2-6 October 2017

ITEMS OF INTEREST

First sunrise of spring season at South Pole -- While residents in the Northern Hemisphere are experiencing shorter daylight following the recent passage of the autumnal equinox, a photograph made by a NOAA Corps officer stationed at the agency's South Pole Atmospheric Baseline Observatory captures the first sunrise of this new spring season (for the Southern Hemisphere) at the South Pole. [NOAA News]
World Space Week is celebrated -- The United Nations General Assembly has declared the week of 4 to 10 October to be "World Space Week" that is designed to "celebrate each year at the international level the contributions of space science and technology to the betterment of the human condition” Last year, more than 2,700 events were held in 86 countries to celebrate the benefits of space and excitement about space exploration. The theme for World Space Week 2017 is “Exploring New Worlds In Space.” we aim to inspire even more events around the world in October 2017. [United Nations]
A Harvest Moon -- A full moon will occur on Thursday, 5 October 2017 at 2:40 PM EDT and 1:40 PM CDT or officially at 1840 Z. This full moon is known as the "Harvest Moon" since it is the full moon nearest the autumnal equinox. The name Harvest Moon originates from a legend that arises the moonlight from the nearly full moon provides mid-latitude farmers with extra natural light for harvesting their crops before the first frost that ends the growing season. Several astronomical factors involving the earth-moon-sun viewing geometry contribute to making this spectacular late summer (or early fall) event special - a large lunar disk that appears as a pumpkin hanging above the eastern horizon just after sunset for several consecutive evenings.
Albuquerque Balloon Fiesta climatology is available -- The world famous Albuquerque International Balloon Fiesta takes place near the beginning of each October; this year the 44th annual event will start this coming Saturday (7 October) and run through 15 October 2017. This nine-day festival involves as many as 750 hot-air balloons and is held over the Rio Grande Valley in the Albuquerque (NM) metropolitan area at this time of year because of the cool nights, sunny days and the lack of thunderstorm activity. Because of the cool autumn nights, the "Albuquerque Box" weather phenomenon occurs, which features light winds from the north near the surface draining down the Rio Grande Valley, while winds from the south aloft permit the balloons to move up and down in this box like feature so as to hover over a small geographic area. The Albuquerque National Weather Service Forecast Office has posted the Balloon Fiesta Climatology that includes the daily temperature and precipitation data for nearly each year of the event along with a further description of the "Albuquerque Box."
Viewing atmospheric circulation in three-dimensions -- Read this week's Supplemental Information.. In Greater Depth for information concerning the average circulation in the lower and upper troposphere.

CLIMATE MONITORING

Monitoring this year's climate across Hawaii and the Pacific Islands -- A "Beyond the Data" blog was recently written for the ClimateWatch Magazine that shows how the weather and climate conditions for Hawaii and the U.S. Affiliated Pacific Islands so far in 2017 compare with long-term averages. Attention is directed to higher than average local sea levels around Hawaii, above-average rainfall totals across many of the US Pacific Islands and above-average sea surface temperatures across large areas of the tropical Pacific. [NOAA Climate.gov News]
New look at new Antarctic iceberg from space -- With the increase in daylight across the Antarctic continent, sensors onboard NASA's Landsat 8 satellite have provided recent visible satellite images of the new massive iceberg that broke off Antarctica's Larsen C ice shelf this past July. [NASA Earth Observatory]
Visualizing climatology of first seasonal snowfall across the nation -- Deke Arndt, Chief of the Climate Monitoring Branch at NOAA's National Centers for Environmental Information (NCEI), wrote a Beyond the Data blog last year describing the interactive map that can be used to see the date by which the chances for the first measurable snowfall (0.1 inches or more) of the season rise to at least 50% at thousands of locations around the nation. These statistics are based upon the US Climate Normals for the 1981-2010 interval calculated by NCEI. Higher elevations in the western states have probably have seen some snow in month of September, while many areas of the Northern Plains and Northern Great Lakes should likely see first snowfalls during the month of October. Deke also showed data plots that how the first dates of snowfall have changed since 1950 at several stations due to changing climate. [NOAA Climate.gov News]

CLIMATE FORECASTS

"Trend" is another factor that affects seasonal forecasting efforts -- A meteorologist with NOAA's Climate Prediction Center (CPC) recently posted an ENSO Blog that focuses upon "climate trends" another factor that his colleagues at CPC consider when producing their monthly and seasonal temperature and precipitation outlooks. These "climate trends" represent the direction and amount that the temperature or precipitation have changed over a sufficient length of time that can help increase the skill in the seasonal predictions, since climate conditions are non-stationary over many decades. [NOAA Climate.gov News]
Third-quarter 2017 Regional Climate Impacts and Outlooks reports released -- During the last week, NOAA and its partners released a series of ten regional climate overviews for the third quarter of 2017 (June through August) that are designed to inform the public of recent climate impacts within their respective regions. In addition, these reports provide regional future climate outlooks that span the three months of October through December 2017. [NOAA NCEI News]
Canadian national seasonal outlook issued -- Forecasters with Environment Canada issued their outlooks for temperature and precipitation across Canada for October, November and December 2017, which represents the last months of meteorological autumn and the first month of meteorological winter. The temperature outlook indicates that nearly all Canada should experience above normal (1981-2010) temperatures for these three months. Only sections of southern British Columbia and Alberta in southwestern Canada, along with a small area of Baffin Island in eastern Canada may have near normal temperatures.
The Canadian precipitation outlook for autumn and early winter of 2017 indicates that above average precipitation could be expected across a large section of Canada stretching from the Prairie Provinces and western Ontario northward to Canadian Archipelago in the Arctic. Sections of Quebec and Labrador in eastern Canada could have above average precipitation. Elsewhere, near average autumn-early winter precipitation was anticipated.
[Note for comparisons and continuity with the three-month seasonal outlooks of temperature and precipitation generated for the continental United States and Alaska by NOAA's Climate Prediction Center, one would need to use Environment Canada's probabilistic forecasts for temperature and precipitation.]

CLIMATE FORCING

Inventorying the increase in bare ground globally -- Scientists from the University of Maryland have been used data collected by NASA's Landsat satellites to determine that the extent of bare ground around the Earth has expanded by approximately 94 thousand square kilometers between 2000 and 2012, primarily the result of human activity. The gain in bare ground is equivalent to loss of vegetative cover. These changes in ground cover can have an impact upon climate. [NASA Earth Observatory]

APPLIED CLIMATOLOGY

Climate science can help the construction industry -- A feature was written for the ClimateWatch Magazine that describes how climate science can be used to help the construction industry save money and manage risk. A new web tool or app called "Climate-I Construction" was developed by a team of scientists at the National Center for Atmospheric Research (NCAR), NOAA and representatives from the construction, insurance, and real estate finance business. This app will allow users to insert the time and place of a construction job, and set thresholds for parameters that matter for the building trade, such as temperature, precipitation and wind. The tool will then provide tailored predictions about the probability of conditions falling above or below the thresholds--too cold to pour concrete, too wet to excavate, too windy to operate a tower crane. [NOAA Climate.gov News]

CLIMATE AND SOCIETY

Bolstering resilience of American Southwest to extreme climate -- The Climate Assessment for the Southwest (CLIMAS) program at the University of Arizona recently received a new five-year, $3.75 million award from NOAA to continue its research on issues related to climate variability in Arizona, New Mexico and northern Mexico. The CLIMAS research will focus on how adaptations and innovations that buffer people from the region's climate — dams, canals, the electric grid and roads — are functioning and how they likely will perform in the future as climate changes. [University of Arizona News]
Earthweek -- Diary of the Planet [earthweek.com]

Concept of the Week: Tropospheric westerly winds, north and south

The theoretical existence of upper tropospheric jet stream winds was not confirmed until being encountered by World War II bomber pilots when heading west into strong headwinds at altitudes of approximately 30,000 feet (10,000 m). Wind speeds sometimes exceeded 170 mph causing their relatively slow, heavily laden aircraft to almost stand still. Subsequently, westerly jet stream winds were found to encircle the planet in midlatitudes of both hemispheres above regions of strong temperature contrasts.

The explanation for these winds involves atmospheric mass distributions and forces on a rotating planet. Air in tropical latitudes is warmed, rises and then flows poleward, both north and south. On a rotating planet, moving air is deflected by the Coriolis effect, to the right in the Northern Hemisphere (and left in the Southern). The greater the temperature differences between warm lower and cold higher latitudes, the stronger the air motions and the faster the jet streams. The vertical temperature patterns result in the highest wind speeds near the top of the troposphere.

So Northern Hemisphere air headed northward, deflected to the right ends up headed east, a "westerly wind." In the Southern Hemisphere, southward moving air, deflected left will also go east, as a westerly wind. These "rivers" of strong upper-level winds steer surface weather systems as they move generally eastward across midlatitudes. They also provide boosts for jet aircraft headed eastward with them, but need to be avoided for going west! Of course, the full story is complex as land (especially mountains) and water surfaces interact with the heating of the air and eddies form in the turbulent flows, so jet streams wander. And with them go the storms and the weather patterns that form our short-term climate.

Historical Events:

2 October 1858...The only tropical cyclone known to produce hurricane-force (estimated) winds on the California coast hit near San Diego, CA. Damage to property is considerable. (The Weather Doctor)
2 October 1980...The temperature at Blue Canyon, CA soared to 88 degrees, an October record for that location. (The Weather Channel)
3 October 1912...The longest dry spell of record in the U.S. commenced as Bagdad, CA went 767 days without rain, ending on 9 November 1914. (David Ludlum)
4 October 1969...Denver, CO received 9.6 inches of snow. October of that year proved to be the coldest and snowiest of record for Denver, with a total snowfall for the month of 31.2 inches. (Weather Channel)
4-7 October 1972...Remnants of Hurricane Joanne brought heavy rain and flooding to much of Arizona. It was the first documented tropical storm to reach the state with its cyclonic circulation intact. Severe flooding occurred in the Clifton, Duncan and Safford areas. (The Weather Doctor)
4 October 1976...The mean wind speed reached 88.5 mph at Melfort, Saskatchewan, the province's highest ever sustained wind. (The Weather Doctor)
4 October 1987...A rapidly deepening coastal storm dumped record snows across eastern New York State and western New England. Grafton, NY was buried under 22 inches of snow, North Springfield, VT had 21 inches and Pownal, VT recorded 18 inches. Most of the snow occurred at higher elevations but even Albany, NY received 6 inches, their earliest measurable snow in 117 years of records. Damage to trees was extensive as many trees were still in full leaf. (The National Weather Summary) (Storm Data) (The Weather Channel) (Intellicast)
In California, high temperatures of 100 degrees at San Francisco, and 108 degrees at Los Angeles and Santa Maria, were October records. San Luis Obispo was the hot spot in the nation with an afternoon high of 111 degrees. (The National Weather Summary).
4 October 1998...As many as 27 tornadoes touched down across Oklahoma, establishing the national record for tornadoes in any state on a single October day. (The Weather Doctor)
4 October 2005...The Minneapolis-St. Paul (MN) International Airport received 4.61 inches, breaking the local daily rainfall record for October. North of the Twin Cities, weather spotters reported nine inches of rain in the town of Spencer Brook. (The Weather Doctor)
5 October 1917...The temperature at Sentinel, AZ soared to 116 degrees F, the highest October temperature ever in the U.S. (National Weather Service files)
6 October 1952...A trace of snow fell at Nashville, TN, the earliest ever on record. (Intellicast)
6 October 1967...Canada's 24-hour rainfall record was established at Ucluelet Brynnor Mines on Vancouver Island in British Columbia with 19.24 in. (Accord Weather Calendar)
6 October 1984...The temperature at Honolulu, HI reached 94 degrees to establish an all-time record at that location. (The Weather Channel)
7 October 1981...Seattle, WA received four inches of rain in 24 hours, a record for the city. (The Weather Channel)
7 October 1987...Tucson, AZ hit 101 degrees for the second day in a row to again equal their record for the month of October. (The National Weather Summary)
7 October 1992...The 2.1 inches of snow that fell at Concordia, KS was the earliest measurable snow on record at that station. (Intellicast )
8 October 1871...Prolonged drought and desiccating winds from the southwest led to the great Chicago fire, the Peshtigo horror, and the Michigan fire holocaust. Fire destroyed more than seventeen thousand buildings killing more than 200 persons in the city of Chicago, while on the same night a fire consumed the town of Peshtigo, WI killing more than 1100 persons. In Wisconsin, a million acres of land were burned, and in Michigan, 2.5 million acres were burned killing 200 persons. "Tornadoes of fire" generated by intense heat caused houses to explode in fire, and burned to death scores of persons seeking refuge in open fields. (David Ludlum) (The Weather Channel)
8 October 1987...Phoenix, AZ reported a record high of 104 degrees and a record tying 116 days of 100-degree weather for the year. Tucson, AZ established an all-time record with 72 days of 100-degree weather for the year. (The National Weather Summary)
8 October 1988...The afternoon high of 80 degrees at Stampede Pass, WA exceeded their previous record for October by seven degrees. (The National Weather Summary)
8 October 1993...With 1.05 inches of rain that fell at Columbia, MO, the yearly total precipitation was pushed to 55.77 inches, breaking the annual record. (Intellicast)

Return to RealTime Climate Portal