CAREER: The role of ecosystem management on boundary layer development and precipitation in the Northern Plains

职业：生态系统管理对北部平原边界层发展和降水的作用

• 批准号: 2034997
• 负责人: Paul Stoy
• 金额: $ 9.22万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-04-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2034997&HistoricalAwards=false
• 关键词: CAREER; role; ecosystem; management; boundary

Global temperatures are rising, largely due to the effects of greenhouse gases from human activities on the amount of radiation from the Sun that is absorbed at the surface of the Earth instead of being reflected back to space. Within this global context are some regional cooling trends that also result from human activity, including those that are beneficial to economic and conservation objectives. One of these cooling trends has been found in the summer in the northern North American Great Plains. Maximum air temperatures have decreased by over three degrees and rainfall has increased by an inch during summer across parts of the Canadian Prairie Provinces since the 1970s. These changes are thought to be due to a decrease in the practice of keeping farm fields fallow during summer; Canada alone has lost around 35 million acres of fallow from the 1970s to the present. The United States has seen a similar decline in fallow area, largely in the Northern Great Plains, but the effects of these changes on regional climate in the U.S. have not been studied to date. Fallow was, and still is, widely practiced to save water for subsequent crops in dry regions, but also increases soil erosion and degradation and is not considered sustainable. Producers have also realized that the water-savings benefit of fallow is often outweighed by the economic losses of not planting a crop. The goal of this project is to understand how agricultural management practices that improve soil conservation and may increase on-farm income can also be beneficial to climate, both now and over the coming decades. As part of the project, a field course will be designed to link Tribal Colleges in the Montana University System with the goal of enhancing STEM education among underrepresented students. Project activities will also enhance existing efforts to improve after-school educational programs at the grade-school level. An inter-university consortium will be designed to coordinate research activities in the atmospheric sciences across Montana, including Tribal Colleges. To understand the role of land management on regional climate, it is necessary to understand the mechanisms by which it influences the climate system, and to integrate this understanding into models that can predict future climate dynamics. In a region with substantial fallow, warm and dry air from near the land surface rises and creates a high and dry atmospheric boundary layer that is unlikely to experience convective precipitation. If plants are present, more moisture and less heat enters the atmosphere, resulting in a moister atmospheric boundary layer that is not nearly as high, which makes cloud formation convective precipitation processes more likely. In this project, the exchange of heat and water between the surface and atmosphere in fallow, grasslands, and crops will be measured, and atmospheric boundary layer development, convective precipitation, and regional climate modeled. Models will be run over the past three decades to understand how management trends have influenced climate and over the forthcoming three decades to understand how future land management changes may, or may not, continue to counter global warming trends.

全球温度正在上升，这在很大程度上是由于人类活动的温室气体对在地球表面吸收的太阳的辐射量的影响，而不是反射回空间。在这种全球背景下，是人类活动的一些区域冷却趋势，包括对经济和保护目标有益的趋势。这些冷却趋势之一是在夏天在北美北美大平原上发现的。自1970年代以来，在加拿大草原省的部分地区，夏季，降雨量的最高温度降低了三个以上，降雨量增加了一英寸。这些变化被认为是由于夏季使农田休耕的实践减少所致。从1970年代到现在，仅加拿大就失去了约3500万英亩的休耕。美国的休养区也有类似的下降，主要在北部大平原上，但是这些变化对美国地区气候的影响迄今尚未被研究。 Fallow曾经并且仍然被广泛实践，以节省干燥地区的水，但也会增加土壤侵蚀和降解，而被认为是可持续的。生产商还意识到，不植物的经济损失通常超过了休耕的水利益。该项目的目的是了解如何改善土壤保护并可能增加农场收入的农业管理实践也可能对现在和未来几十年中的气候有益。作为该项目的一部分，将设计一门实地课程，以将蒙大拿大学系统中的部落学院联系起来，以增强代表性不足的学生的STEM教育。项目活动还将加强现有的努力，以改善学院级别的课后教育计划。大学间财团将旨在协调蒙大拿州大气科学的研究活动，包括部落学院。要了解土地管理对区域气候的作用，有必要了解它影响气候系统的机制，并将这种理解整合到可以预测未来气候动态的模型中。在一个有大量休耕，温暖和干燥空气附近的区域中，陆地表面升起，并产生高而干燥的大气边界层，不太可能经历对流降水。如果存在植物，则更多的水分和更少的热进入大气，从而导致一个不高的大气边界层，这使得云形成对流的降水过程的可能性更高。在这个项目中，将测量耕种，草原和农作物之间的表面和大气之间的热量和水交换，以及大气边界层的发展，对流降水和所建模的区域气候。模型将在过去三十年中运行，以了解管理趋势如何影响气候以及即将到来的三十年，以了解未来的土地管理变化如何或可能不会继续应对全球变暖趋势。