研究发现气温升高与美国枪击暴力案件激增有着密切关系

美国百城日温度与枪袭相对风险（RR）的累积关联图，来源：Boston University

从费城到波特兰，在暖和的日子里，美国各地的城市都在经历枪支暴力的激增。From Philadelphia to Portland, cities across the United States are experiencing spikes in gun violence on warm days.

目前，波士顿大学公共卫生学院和华盛顿大学社会工作学院的一项新研究首次将热引发的枪击事件问题在全美国范围进行了分析。Now, a new study by Boston University School of Public Health and the University of Washington School of Social Work provides a first-of-its-kind analysis of heat-attributable shootings as a nationwide problem.

这项研究发表在《美国医学会网络公开》杂志上，在该国人口最多的100个城市里，气温升高与枪击风险升高之间存在着固定关系。Published in the journal JAMA Network Open, the study found a consistent relationship between higher temperatures and higher risk of shootings in 100 of the country's most populated cities.

调查结果显示：在遇到比常温偏高的天气时，美国东北部和中西部这两个地区的枪支暴力案件增幅最大。The findings indicate that the Northeast and Midwest regions experience the sharpest increases in gun violence on hotter-than-normal days.

全球性气候恶化可能会令气温升得更高，研究人员表示：这些发现旨在警醒人们去制定持之以恒的的措施和计划，使社区适应更热的气候，从而减低高温所引发的枪支暴力带来的风险。As climate change threatens to raise daily temperatures even more, the researchers say these findings underscore the need for ongoing policies and programs that acclimate communities to heat and mitigate the risk of heat-attributable gun violence.

在这项研究中，Jay博士、Lyons博士和他们的同事参考了枪支暴力档案馆的公开数据。该团队分析了2015~2020年间每一日的气温和所发生的116000多起枪击事件——这些事件发生在美国遭遇枪击事件最多的前100个城市。For the study, Dr. Jay, Dr. Lyons, and colleagues utilized publicly available data from the Gun Violence Archive, a national repository of gun violence information. The team analyzed daily temperatures and more than 116,000 shootings from 2015 to 2020, in the top 100 US cities with the highest number of assault-related shootings in the country.

排除掉季节和地区的气候差异，他们发现其中有7973起枪击事件归因于高于日平均气温的的温度，尽管这些城市间气温相差很大。Accounting for seasonality and regional climate differences, they found that 7,973 shootings were attributable to above-average temperatures. The temperatures associated with increased gun violence varied considerably across cities.

例如，在气温飙升至日平均气温的第96百分位范围内的日子里，西雅图和拉斯维加斯枪支暴力风险飙升最多——西雅图的对应气温为84华氏度（约为28摄氏度），而拉斯维加斯的对应气温则为104华氏度（约为40摄氏度）。 For example, both Seattle and Las Vegas experienced the highest elevated risk of gun violence during days when the temperature soared within the 96th percentile range of average daily temperatures—but for Seattle, that temperature was 84 degrees, while in Las Vegas, it was 104 degrees.

Lyons博士说：“枪支暴力高发的城市应持续广泛实施枪支预防措施，包括可靠信使计划和植根医院的暴力干预计划。” "Cities with high rates of firearm violence should continue to implement firearm-prevention strategies broadly including credible messenger programs and hospital-based violence intervention programs," Dr. Lyons says.

研究建议：那些因热引发过更多枪击暴力的城市应在社区层面实施热适应措施，譬如增加绿化率来减少城市热岛效应。The study suggests that for cities with more heat-attributable shootings, implementing heat adaptation strategies at the community level—such as greening efforts that have been effective at reducing urban heat islands.

那么，是什么引发了高温和枪支暴力之间的联系呢？Jay博士认为可能是热量引起压力，使人们更加具有攻击性。也可能因为人们在天气暖和的时更喜欢外出，人与人之间有了更多互动，便有更多机会产生冲突和暴力。两个原因极有可能兼而有之。”So what might be driving this association between heat and gun violence? "It could be that heat causes stress, which makes people more likely to use aggression," Dr. Jay says. "Or it could be that people are more likely to get out on warmer days and have more interactions, which creates more opportunities for conflict and violence. Most likely, it's a combination of both."

从地区来看，热引发的枪支暴力案例在美国东北部和中西部地区很可能最多，原因是这些地区的气温波动更大，又或者这些地区的居民对炎热的适应程度较低——不过但这些地区的种族隔离现象也比其他地区更严重。Regionally, heat-attributable gun violence may be most pronounced in the Northeast and Midwest due to sharper fluctuations in temperature in those areas, or because cities in those regions are less acclimated to heat. But those regions are also more racially segregated than other areas of the country.

杰伊博士说：“据我们所见，按种族来分，美国东北部和中西部地区在建筑环境和其他资源方面存在最大的差异化。”。“我们了解到：种族隔离和撤资使有色人种，尤其是黑人的社区，更容易暴露在导致枪支暴力风险的不利环境下，这些环境包括废弃的建筑、酒类商店、缺乏绿地的居住环境和聚堆的城市热岛。”"The Northeast and Midwest regions are where we see some of the starkest differences in the built environment and other resources, according to race，" Dr. Jay says. "We know that segregation and disinvestment lead communities of color, especially Black communities, to have greater exposure to adverse environmental conditions that contribute to gun violence risk, such as abandoned buildings, liquor stores, lack of green space, and more intense urban heat islands."

（编译：谷雨，新闻来源：medicalxpress.com）