The line graph illustrates changes in the average monthly temperatures across three major cities during one specific year.
Overall, the temperatures in Boston and Paris slightly increased over the period in question, albeit with some fluctuations, while Melbourne remained relatively stable. Notably, in contrast to the other two cities, Melbourne was hotter during the winter months and cooler in the summer.
Paris and Boston exhibited remarkably similar temperature trajectories. Commencing in January at around 4 degrees, Boston recorded its trough point among the three cities, after which the temperature ascended to a zenith of around 33 degrees by July, registering an eightfold increase. Meanwhile, Paris had experienced a notable rise from about 8 to 24 degrees up until July, tripling its initial point before plateauing for a month. However, from that point onward, both cities witnessed a gradual yet uninterrupted decline, ending the year at around 5 and 9 degrees, respectively.
Melbourne, on the other hand, bucked the foregoing trend in that it remained relatively stable during the timeframe. Although the temperature there in January stood at 25 degrees, it gradually dwindled until July, when the other two cities overtook Melbourne in this regard. Afterwards, however, a moderate rebound ensued in the temperature levels, eventually surpassing the other cities and reaching the same level as at the start of the year.