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Kelly Helm Smith
,
Andrew J. Tyre
,
Zhenghong Tang
,
Michael J. Hayes
, and
F. Adnan Akyuz

Abstract

State climatologists and other expert drought observers have speculated about the value of monitoring Twitter for #drought and related hashtags. This study statistically examines the relationships between the rate of tweeting using #drought and related hashtags, within states, accounting for drought status and news coverage of drought. We collected and geolocated tweets, 2017–18, and used regression analysis and a diversity statistic to explain expected and identify unexpected volumes of tweets. This provides a quantifiable means to detect state-weeks with a volume of tweets that exceeds the upper limit of the prediction interval. To filter out instances where a high volume of tweets is related to the activities of one person or very few people, a diversity statistic was used to eliminate anomalous state-weeks where the diversity statistic did not exceed the 75th percentile of the range for that state’s diversity statistic. Anomalous state-weeks in a few cases preceded the onset of drought but more often coincided with or lagged increases in drought. Tweets are both a means of sharing original experience and a means of discussing news and other recent events, and anomalous weeks occurred throughout the course of a drought, not just at the beginning. A sum-to-zero contrast coefficient for each state revealed a difference in the propensity of different states to tweet about drought, apparently reflecting recent and long-term experience in those states, and suggesting locales that would be most predisposed to drought policy innovation.

Free access
Kelly Helm Smith
,
Andrew J. Tyre
,
Zhenghong Tang
,
Michael J. Hayes
, and
F. Adnan Akyuz
Full access
Karsten A. Shein
,
Dennis P. Todey
,
F. Adnan Akyuz
,
James R. Angel
,
Timothy M. Kearns
, and
James L. Zdrojewski

Abstract

The NOAA National Climatic Data Center maintains tables for temperature and precipitation extremes in each of the U.S. states. Many of these tables were several years out of date, however, and therefore did not include a number of recent record-setting meteorological observations. Furthermore, there was no formal process for ensuring the currency of the tables or evaluating observations that might tie or break a statewide climate record. This paper describes the evaluation and revision of the statewide climate-extremes tables for all-time maximum and minimum temperature, greatest 24-h precipitation and snowfall, and greatest snow depth (the five basic climate elements observed on a daily basis by the NOAA Cooperative Weather Network). The process resulted in the revision of 40% of the values listed in those tables and underscored both the necessity of manual quality-assurance methods and the importance of continued climate-monitoring and data-rescue activities to ensure that potential record values are not overlooked.

Full access
Karsten A. Shein
,
Dennis P. Todey
,
F. Adnan Akyuz
,
James R. Angel
,
Timothy M. Kearns
, and
James L. Zdrojewski

New all-time extreme climate records have been set in several states over the past few years. These records highlighted a need to review the existing statewide climate extremes tables maintained by the NOAA National Climatic Data Center (NCDC). Also, since these tables were last up-dated, NCDC has greatly extended its digital data record into the past for many locations and has applied improved quality assurance processes to its archived data, revealing several potential new record values. To ensure the records maintained in the statewide climate extremes tables accurately reflect the most current and valid data available, the records were reevaluated. The all-time maximum and minimum temperature, all-time greatest 24-h precipitation and snowfall, and all-time greatest snow depth for each of the 50 states, Puerto Rico, and the U.S. Virgin Islands were manually examined to determine their validity, accuracy, accessibility, and provenance. NCDC's data holdings were scoured for values that might exceed established records, and the validity of each potentially record-breaking observation was evaluated. The revised extremes tables were vetted by the National Weather Service, regional climate centers, and state climatologists to ensure agreement. In conjunction with this revision, a new state climate extremes evaluation process has been established to formally consider any potential challenges to the existing records and update the records tables as necessary.

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Andrew Hoell
,
Britt-Anne Parker
,
Michael Downey
,
Natalie Umphlett
,
Kelsey Jencso
,
F. Adnan Akyuz
,
Dannele Peck
,
Trevor Hadwen
,
Brian Fuchs
,
Doug Kluck
,
Laura Edwards
,
Judith Perlwitz
,
Jon Eischeid
,
Veva Deheza
,
Roger Pulwarty
, and
Kathryn Bevington

Abstract

The 2017 flash drought arrived without early warning and devastated the U.S. northern Great Plains region comprising Montana, North Dakota, and South Dakota and the adjacent Canadian Prairies. The drought led to agricultural production losses exceeding $2.6 billion in the United States, widespread wildfires, poor air quality, damaged ecosystems, and degraded mental health. These effects motivated a multiagency collaboration among academic, tribal, state, and federal partners to evaluate drought early warning systems, coordination efforts, communication, and management practices with the goal of improving resilience and response to future droughts. This essay provides an overview on the causes, predictability, and historical context of the drought, the impacts of the drought, opportunities for drought early warning, and an inventory of lessons learned. Key lessons learned include the following: 1) building partnerships during nondrought periods helps ensure that proper relationships are in place for a coordinated and effective drought response; 2) drought information providers must improve their understanding of the annual decision cycles of all relevant sectors, including, and beyond, direct impacts in agricultural sectors; and 3) ongoing monitoring of environmental conditions is vital to drought early warning, given that seasonal forecasts lack skill over the northern Great Plains.

Full access
Andrew Hoell
,
Britt-Anne Parker
,
Michael Downey
,
Natalie Umphlett
,
Kelsey Jencso
,
F. Adnan Akyuz
,
Dannele Peck
,
Trevor Hadwen
,
Brian Fuchs
,
Doug Kluck
,
Laura Edwards
,
Judith Perlwitz
,
Jon Eischeid
,
Veva Deheza
,
Roger Pulwarty
, and
Kathryn Bevington
Full access