了解融雪

作者：Renata BarradasGutiérrez

Regions of the Canadian Arctic are experiencing unprecedented warming as a result of the greenhouse gases emitted by human activity. The western Arctic specifically has experienced significant increases in near surface ground temperatures over the past few decades, almost twice that of the global average temperature increase. This warming trend has resulted in significant changes to the regional ecosystems and the physical processes operating across these environments.

为了更好地了解在进一步的气候变化情况下如何做出反应，由菲利普·马什（Philip Marsh）博士领导的加拿大威尔弗里德·劳里尔大学（Wilfrid Laurier University）的Marsh Lab Trail Valley Creek（TVC）研究小组菲利普·马什（Philip Marsh）旅行超过4,000公里，研究了变化的水文学变化。of Canada’s western Arctic using Leica Geosystems GNSS instruments. The research collects data on all components of the water cycle and aims to understand how further temperature increases will affect the local and regional freshwater systems by combining:

• detailed field observations
• 遥感
• GNSS定位和建模。

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Survey time

将水作为雪的年度输入是水文循环的最重要方面，也是北极流和湖泊系统的最大淡水贡献者。在冬季结束时，在4月至五月中旬之间，沼泽实验室TVC研究人员进行了雪调查，测量了多个研究盆地的雪深和储水。一组研究人员准确地测量了在冬季积累的年度降雪，以量化液体水储存量（以雪水等效量为单位），并计算一旦雪融化，水文系统可用的水量。

To better understand the heterogeneous nature of the tundra snow cover, Marsh Lab TVC researchers use many recent technological advances, including:

• 无人驾驶汽车（UAV）
• 空中雪深度数据
• 自动雪深度记录探针
• 实验宇宙射线中子探针站。

The team of researchers currently uses two Leica GS10 GNSS receivers and two CS20 field controllers to collect point type data for a wide variety of research projects. With Leica Captivate field software, the team collects and organises the data while Leica Infinity survey software is used to project and filter the collected field points, ensuring data is stored in the correct coordinate system. UAV post processing software is also used.

威尔弗里德·劳里尔大学（Wilfrid Laurier University）的研究助理布兰登·沃克（Branden Walker）表示：“我们的现场工作在很大程度上依赖于获得高精度的空间数据集，而我们的Leica Geosystems GNSS系统使所有这一切都成为可能。”“以前在其他研究站点使用Leica Geosystems仪器，结果出色，我们选择再次与他们一起参加该项目。”

研究人员组还使用GS10 GNSS接收器和CS20现场控制器来定期测量地面控制点，并对地形验证和变化多年冻土特征的检测进行调查。

沃克说：“我们正在进行的研究项目的大多数集中在获得高度精确和准确的GPS数据上。”“与其他数据集相比，Leica Geosystems GNSS系统已被证明可以提供强大而可靠的数据。”

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在上方和下方收集数据表格

测量较大区域雪的主要方法之一是通过实验使用无人机。为了验证，地理连接和纠正UAV中的GNSS数据，MARSH LAB TVC研究人员需要使用Leica GeoSystems GNSS系统测量地面上的实际雪和地面高度准确性水平。然后在Infinity调查软件和摄影测量软件中处理这些高度精确的地面控制点，以提高无人机映射点的准确性。

“The Leica Geosystems GNSS system we use allows us to create ground control points with a known position with sub-centimetre accuracy. This is very important for correcting our elevation products from the UAV, which may only differ from one flight to the next by a few centimetres,” said Walker. “This data allows us to quantify snow depth and water storage with previously unobtainable spatial and temporal resolutions. The data from our UAV is post processed and georeferenced using ground control points collected with our Leica RTK system to produce highly precise and accurate spatial datasets.

“我们的Leica Geosystems仪器是我们研究计划的骨干。我们的GNSS仪器提供的精度和准确性提供了使用UAV绘制小规模变化所需的空间数据，并帮助我们在设置和收集数据点时可以节省现场的时间。”

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帮助地球的水图任务

MARSH LAB TVC研究人员使用Leica GeoSystems GNSS系统进行的研究也将是北美空气地表水和海洋地形（AIRSWOT）的主要地面验证，这是NASA的NASA北极硼脆弱性实验的组成部分（上图）。Airswot验证任务测量了航班期间尽可能多的湖泊上水的表面高度。Airswot是SWOT任务的一部分，该任务是从空间中绘制地球的水，以了解地球上有多少淡水并计算河流流量并监测沿海洋流。

NASA’s AirSWOT Phenomenology airborne radar flies across Northern Canada and Alaska measuring the Water Surface Elevation of tens of thousands of water bodies larger than 250 metres across. For the AirSWOT mission, the team has a small window to capture the measurements needed so they must have quick and reliable GNSS instruments that are capable of measuring from a long distance range from the base.

“The reliability of the rover to make quick and accurate measurements several kilometres from the base gives me confidence we will be able to validate NASA’s AirSWOT data successfully,” said Evan Wilcox, MSc Geography Candidate at Wilfrid Laurier University.

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Training field researchers

Marsh Lab TVC接待了来自北美和欧洲研究加拿大北极地区的研究小组。Wilfrid Laurier的研究人员会定期帮助培训学生研究人员如何使用Leica Geosystems产品。bob综合app下载

“成为大学LED研究小组的一部分也导致了一个很高的学生转身，因此，Leica Geosystems产品的简单性和直观设计使培训下一轮的现场研究人员和学生变得更加容易 - 再次，节省了我们的小组时间和金钱bob综合app下载长期。”沃克补充说。

此外，恶劣的北极条件可以推动大多数设备的限制。Leica Geosystems GNSS接收器和CS20场控制器设计为在最极端的条件下执行。

沃克说：“我们的现场工作的性质将所有工具都带到了它们的绝对突破点和最大程度上。”“我们的Leica GNSS系统已经在各种恶劣的北极条件下工作，包括-20°Celsius的温度。”

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关于气候变化的可靠信息

备份与徕卡的准确度和精密度Geosystems, the group of researchers are gaining a greater understanding on how the Arctic tundra systems have changed in response to increased air temperatures resulting from climate change. Accurate and reliable data is needed to better understand the complex relationship between snow depth, rain, lake levels, vegetation, permafrost and streamflow, and the physical processes at play to be able to predict future changes using mathematical models.

目前，众多研究科学家和研究生正在使用这项研究生成的数据，重点是测试和验证新的数据收集技术。获得的信息还为一个长期的研究项目做出了贡献，该项目收集了北极苔原的历史数据集。了解北极的水文过程将提供有关气候变化如何封闭湖泊，溪流和积雪的可靠信息，以及这如何影响加拿大人的生活。