World Meteorology Day: India adopts new standard for kilogram, changes textbooks

India on Monday adopted a global resolution to redefine four of the seven base units — kilogramme, Kelvin, mole and ampere, a move expected to have far-reaching effects, including changes in textbooks. A resolution to redefine four of the seven base units was passed by representatives of 60 countries at the General Conference on Weights and Measures (CGPM) of the International Bureau of Weights and Measures (BIPM), Paris on 16 November last year. However, it has been implemented across the world on 20 May — **World Meteorology Day** , Shekhar Mande, Director General of the Council for Scientific and Industrial Research (CSIR), said. Over 100 countries have adopted the metric system of measurements, also known as the International System of Units (SI), which has been in practice since 1889. The other base units are — second, metre and candela. [caption id=“attachment_6674651” align=“alignnone” width=“1280”] Metric standards in the Rijksmuseum. Image credit; Wikimedia Commons[/caption] “The fundamental constants are invariants of time and space and have successfully replaced the artefact based units, and aptly opened up the new era for quantum world by linking all seven base units to fundamental constants or quantum standards,” said K Aswal, Director of the National Physical Laboratory (NPL), one of the oldest scientific institutes in the country that also takes care of setting meteorology standards domestically. The purpose of a system unit is to enable worldwide coherence of measurements. The **International System of Units** (SI) was formalised in 1960 and has been updated several times to account for development in measurement technology. [caption id=“attachment_5586311” align=“alignnone” width=“1280”] A prototype kilogram replica on display at a Paris Museum, featuring three layers of protective glass. Image courtesy: Jabs 88[/caption] “Since the 1960s, we have to rely ever more heavily on advanced science and engineering in our day-to-day lives, and also in manufacturing, healthcare and science. The proposed changes in the unit definition have been designed to have no immediate consequences,” he said. “The unit redefinitions represent a profound change of perspective and they are expected to form the foundations of improved measurements for decades to come as science and technology continues to develop in a way we cannot currently foresee,” Aswal said, however, this “may not change anything drastically”, but it will matter when it comes to measurements less than a kilogramme. For instance, measuring smaller diamonds. The NPL has also sent recommendations on the proposed changes to be incorporated in the National Council of Educational Research and Training (NCERT) to implement them in contemporary education, he said. Recommendations on the proposed changes have also been sent to the All India Council for Technical Education (AICTE), Indian Institutes of Technology (IITs), National Institutes of Technology (NITs), and other academic institutes to be incorporated in syllabi of metrology courses in graduate engineering and academic courses.