Category: Featured Database

Author: Pokharel, B.; Wang, S. Y. S.; Meyer, J.; Gillies, R. & Lin, Y.-H. Description: The 1-in-1000-year precipitation event in late June 2016 over West Virginia caused tremendous flooding damage. Like the 2012 mid- Atlantic derecho that blacked out much of the DC area, similar events can be traced to small, mid-tropospheric perturbations (MPs) embedded in the large-scale ridge pattern. Under this “weakly-forced” pattern, severe weather outbreaks commonly occur alongside eastward propagating MPs acting as a triggering mechanism for progressive mesoscale convective systems, which move across the central and eastern…

Author: Rahmani, V.; Hutchinson, S. L.; Harrington John A., J. & Hutchinson, J. M. S. Description: Climate variability and change can impact rainfall by varying time, location, magnitude, and frequency of precipitation events. Fluctuations in heavy rainfall events can impact flooding and drought events and water management systems. This research addresses temporal and spatial distributions of extreme daily and monthly rainfall in Kansas using daily rainfall data from 23 stations for the period 1890–2013. The Mann–Kendall non‐parametric method was used in trend analysis. Results indicate an increasing trend in the…

Author: Kretschmer, M.; Coumou, D.; Agel, L.; Barlow, M.; Tziperman, E. & Cohen, J. Description: The extratropical stratosphere in boreal winter is characterized by a strong circumpolar westerly jet, confining the coldest temperatures at high latitudes. The jet, referred to as the stratospheric polar vortex, is predominantly zonal and centered around the pole; however, it does exhibit large variability in wind speed and location. Previous studies showed that a weak stratospheric polar vortex can lead to cold-air outbreaks in the midlatitudes, but the exact relationships and mechanisms are unclear. Particularly,…

Author: Pendergrass, A. G. & Knutti, R. Description: A few days with heavy rain contribute disproportionately to total precipitation, while many days with light drizzle contribute much less. What is not appreciated is just how asymmetric this distribution is in time, and the even more asymmetric nature of trends due to climate change. We diagnose the temporal asymmetry in models and observations. Half of annual precipitation falls in the wettest 12 days each year in the median across observing stations worldwide. Climate models project changes in precipitation that are more…

Author: Cohen, J.; Pfeiffer, K. & Francis, J. A. Description: Recent boreal winters have exhibited a large-scale seesaw temperature pattern characterized by an unusually warm Arctic and cold continents. Whether there is any physical link between Arctic variability and Northern Hemisphere (NH) extreme weather is an active area of research. Using a recently developed index of severe winter weather, we show that the occurrence of severe winter weather in the United States is significantly related to anomalies in pan-Arctic geopotential heights and temperatures. As the Arctic transitions from a relatively…

Author: Fortunato, D. Description: Objective: Laws reducing hurdles to legally carrying concealed firearms are argued to have a deterrent effect on crime by increasing its perceived costs. This argument rests on the assumption that these policies will either directly or indirectly increase the perceived distribution of firearm carriers, an assumption that is as yet untested. This article tests this assumption and, in so doing, suggests testing the necessary conditions of policy can be useful when assessing outcomes is difficult. Methods: I collect survey data on the perceived number of firearm…

Author: Hamill, M. E.; Hernandez, M. C.; Bailey, K. R.; Zielinski, M. D.; Matos, M. A. & Schiller, H. J. Description: Over the last 30 years, public opinion and state level legislation regarding the concealed-carry of firearms have shifted dramatically. Previous studies of potential effects have yielded mixed results, making policy recommendations difficult. We investigated whether liberalization of state level concealed-carry legislation was associated with a change in the rates of homicide or other violent crime. Data on violent crime and homicide rates were collected from the US Department of…

Author: Rosati, A. G.; Hagberg, L.; Enigk, D. K.; Otali, E.; Emery Thompson, M.; Muller, M. N.; Wrangham, R. W. & Machanda, Z. P. Description: Humans prioritize close, positive relationships during aging, and socioemotional selectivity theory proposes that this shift causally depends on capacities for thinking about personal future time horizons. To examine this theory, we tested for key elements of human social aging in longitudinal data on wild chimpanzees. Aging male chimpanzees have more mutual friendships characterized by high, equitable investment, whereas younger males have more one-sided relationships. Older…

Author: Pennycook, G. & Rand, D. G. Description: Reducing the spread of misinformation, especially on social media, is a major challenge. We investigate one potential approach: having social media platform algorithms preferentially display content from news sources that users rate as trustworthy. To do so, we ask whether crowdsourced trust ratings can effectively differentiate more versus less reliable sources. We ran two preregistered experiments ( = 1,010 from Mechanical Turk and = 970 from Lucid) where individuals rated familiarity with, and trust in, 60 news sources from three categories: (…

Author: Bennett, W. L. & Livingston, S. Description: Many democratic nations are experiencing increased levels of false information circulating through social media and political websites that mimic journalism formats. In many cases, this disinformation is associated with the efforts of movements and parties on the radical right to mobilize supporters against centre parties and the mainstream press that carries their messages. The spread of disinformation can be traced to growing legitimacy problems in many democracies. Declining citizen confidence in institutions undermines the credibility of official information in the news and…