Google Earth - a user friendly device for practical ground and aerial survey of the Earth

Herojit Nongmaithem *

Google - a word so common to all initially came up in 1998 as a private company and Larry Page & Sergey Brin were the founders even when they were Ph. D. scholars of Standford University, California. Today it has been rated as one of the biggest multinational technology company amongst the big four - Amazon, Apple & Facebook. It grew enormously and came up with a chain of products, acquisitions, and partnerships beyond Google’s core search engine (Google Search).

Services designed for work and productivity (Google Docs, Google Sheets, and Google Slides), email (Gmail/Inbox), scheduling and time management (Google Calendar), cloud storage (Google Drive), instant messaging and video chat (Google Allo, Duo, Hangouts), language translation (Google Translate), mapping and navigation (Google Maps, Waze, Google Earth, Street View), video sharing (YouTube), note-taking (Google Keep), and photo organizing and editing (Google Photos) are some of them.

The company leads the development of the Android mobile operating system, the Google Chrome web browser, and Chrome OS, a lightweight operating system based on the Chrome browser. The Google.com is the most visited website in the world.

Amongst the company’s endless products, the most commonly used by the scientific community for having the first hand information of any location is the Google Earth. Such initial information and results for any part of the earth can be easily interfaced to most of the geographic information system (GIS) softwares which ultimately can be linked to many prioritised scientific researches. To define it, Google Earth is a system based program that renders 3D representation of Earth based primarily on satellite imagery.

The program maps the Earth by superimposing satellite images, aerial photography, and GIS data onto a 3D globe, allowing users to see every location and landscapes from various angles. Users can explore the globe by entering addresses, name of any location and geographic coordinates, or by using any input keys once it’s operational in the desktop versions.

The app is also available for the smart phones as well and specially meant for navigation purposes. Imagery resolution used in Google Earth ranges from 15 metres of resolution to 15 centimetres. For much of the Earth, Google Earth uses digital elevation model data collected by NASA’s Shuttle Radar Topography Mission. This creates the impression of three-dimensional terrain, even where the imagery is only two-dimensional.

Special features of Google Earth provide a series of other tools through the desktop application. This utility helps one to analyses the terrain condition, morphological and physiographical set up, features of regional scale; streams, river systems, mountains, deltas, plains, plateaus, etc.

The time lapsed images of a same area further provide the opportunity to assess the temporal change whether it be the forest, roads, landslides and even the cloud coverage. Additional globes for the Moon and Mars are available, as well as a tool for viewing the night sky. A flight simulator game is also included.

Other features allow users to view photos from various places uploaded to Panoramio, information provided by Wikipedia on some locations, and Street View imagery. The web-based version of Google Earth also includes Voyager, a feature that periodically adds in-program tours, often presented by scientists and documentarians.

Google Earth shows 3D building models in some cities, including photorealistic 3D imagery. The first 3D buildings in Google Earth were created using 3D modeling applications such as SketchUp and, beginning in 2009, Building Maker, and were uploaded to Google Earth via the 3D Warehouse. Till February, 2019 entire North America, Japan, Australian New Zealand, parts of South America, Europe, South Africa, Egypt, islands along the East Pacific ocean have 3D coverage Antartica being the only left out continent.

Since 2009, the Google Ocean feature allows users to zoom below the surface of the ocean and view the 3D bathymetry. Supporting over 20 content layers, it contains information from leading scientists and oceanographers. In June 2011, Google increased the resolution of some deep ocean floor areas from 1-kilometre grids to 100 metres. The sharper focus is available for about 5 percent of the oceans like in the Hudson off New York City, the Wini Seamount near Hawaii, and the Mendocino Ridge off the U.S Pacific coast.

Discussing a practical use of Google Earth is that one can easily visualize the scenic beauty and adventurous route, the steep gradients of Shirui Peak, aerial view of Loktak Lake within few minutes. One can even map the boundary of each constituency, municipal corporation -zila parisad jurisdictions. Planning and execution of any developmental programme can be easily geo tagged and verified using it.

Because of its portability (mobile//tablet/laptop) and user friendly nature even a commoner can do many findings that are immensely helpful for local administrations, environmentally based NGO’s, teachers and students for study projects.

A vivid example of the time lapsed images (2009-19) of the Langol reserve forest and surrounding area clearly showed the emergence of new NIT complex during the last decade.

Despite its manifold utilities, it has been viewed by some as a threat to privacy and national security, leading to the program being banned in many countries. Some countries have requested that certain areas be obscured in Google’s satellite images, usually areas containing military facilities. Many a times, the NASA’s satellite even forgoes the international and national boundaries of the Indian Government which can be misleading to the common masses.

When zoomed in much detail, the satellite images and aerial photos have mismatched boundaries due to differences in the date of the images. Names of many places are in American language hence drastically different with the local ones. 3D viewing and terrain analyses also require some training otherwise the first time users can develop pseudo visuals.

Considering the pros and cons, Google Earth is every geoscientist’s first choice of foundational research of any part of the earth. The best part is that the programme is freeware and anyone can access it with the internet connectivity.