Daniel Pavlinovic WEATHER CLIMATE WATER UNDERSTANDING WORLD METEOROLOGICAL DAY public.wmo.int/en/WorldMetDay2017 23 MARCH 2017 INTRODUCING THE NEW ON-LINE EDITION OF THE INTERNATIONAL ATLAS

Understanding clouds is the theme of World Meteorological Day 2017 to highlight the Advances in science, technology and photography prompted WMO to undertake enormous importance of clouds for weather, climate and water. Clouds are central to the ambitious and exhaustive task of revising and updating the Atlas with images weather observations and forecasts. Clouds are one of the key uncertainties in the contributed by meteorologists, cloud watchers and photographers from around study of climate change: we need to better understand how clouds affect the climate the world. and how a changing climate will affect clouds. They play a critical role in the water cycle and in shaping the global distribution of water resources.

On the lighter side, World Meteorological Day 2017 will provide an opportunity to cele- brate the inherent beauty and aesthetic appeal of clouds, which have inspired artists, poets, musicians, photographers and countless other enthusiasts throughout history.

World Meteorological Day marks the launch of a new edition of the International Cloud Atlas after the most thorough and far-reaching revision in its long and distinguished history. The new WMO Atlas is a treasure trove of hundreds of images of clouds, including a few newly classified cloud types. It also features other meteorological phenomena such as rainbows, halos, snow devils and hailstones. For the first time ever, the Atlas has been produced in a digital format and is accessible via both computers and mobile devices.

The International Cloud Atlas is the single authoritative and most comprehensive reference for identifying clouds. It is an essential training tool for professionals in the meteorological community and those working in aviation and shipping. Its reputation is legendary among cloud enthusiasts.

The International Cloud Atlas has its roots in the late nineteenth century. It was revised on several occasions in the twentieth century, most recently in 1987, as a hard-copy

book, before the advent of the Internet. Gary McArthur

Newly added supplementary feature , Burnite, Tasmania, Australia Luka Filipi New species, Volutus (roll cloud), Szprotawa, Poland Volutus (roll Szprotawa, cloud), species, New Germany, Keilberg, Mt. halo, photometeor illustrated Newly Austria, Jois, homomutatus, stratiformis Cirrocumulus top: from Clockwise

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Jan Knight Serra de Alvorge, Portugal Alvorge, de Serra flammagenitus flammagenitus),(Cumulus term cloud special added Newly Communications and Public andPublic Communications Affairs Office For pleasecontact: moreinformation, public.wmo.int as as

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