The night blossoming heater, like some wild weed, has invaded sidewalks cafes and pizza places in Sydney. During the day they are mostly mere observors, small metallic umbrellas that are short on shade. By night they flare up, big bunsen burners, radiant efflorescence of blue, yellow and red.  While they make pavement tables a cosier proposition, I am not sure about all that heat being pumped out into the plein air, warming mostly ones face. Though one looks less chic, wrapped in  the rugs put out by many thoughtful cafes, I think it might be less taxing on our climate.