You want to dig down, let's do that... at the scale of molecules, there is no such thing as temperature. What we measure as temperature is the average velocity of molecules in a substance. So, in a cup of freshly made hot coffee, you can expect molecules to be moving on average faster than the average velocity of molecules in a cold glass of water. Does this mean all the molecules in the coffee are moving faster than the molecules in the glass of cold water? No, in fact there are molecules in the cold glass of water there are moving faster than the molecules in the hot cup of coffee, but when you refer to the temperature of an object, you don't talk about the individual velocities of molecules, you don't talk about a set of molecules, you have to refer to the average of all the molecules in that thing. We measure the average velocity of molecules using "temperature". The faster the molecules move, the higher the temperature. On zero-scale units like Kelvin and Rankine, 0 refers to molecules standing still. On offset units like Celsius and Fahrenheit, the value where molecules are stationary is a negative value because when people came up with the units Celsius and Fahrenheit they didn't know the nature of temperature, they did not know it was a measure of random motion of molecules, but these scales are still valid for measuring temperature as much as Kelvin and Rankine. The article says sunday was hottest recorded day on earth. That means on that day, the molecules on earth were moving on average faster than ever before recorded. The fact that molecules don't have temperature does not negate the measurement of temperature of the planet.
Next, HOW is the planet getting this warm? Even if we put all the human made heating appliances, cars, trains, planes, ships and nuclear bombs together, we still wouldn't be able to increase the temperature of the earth by 1 degree because earth is huge and we're tiny. BUT, the energy from the sun bathes the earth every single day with a thousand times more energy than all of humanity released in the past millennia. This is an insane amount of energy that completely dwarfs all human activity since the dawn of time. It has been doing that for a very long time and it's been in equilibrium, where the energy coming in is the same as the energy being radiated out into space. But what happened recently is that by changing the atmosphere slightly we made earth retain a tiny percentage more of the energy that hits it. CO2 alone went from 0.02% in preindustrial times to 0.04% that seems like not much, right? What would 0.02% increase in CO2 do?? It's so TINY... but that 0.02% is capturing 0.02% more of the energy sun is sending to earth... the thousand times more energy than all of humanity ever used... 0.02% of it is still many times more energy than humanity ever produced, and that's just CO2. If you add CFC, methane, etc, you end up with a much dire situation where we've changed the planet to retain energy equivalent to several thousand hiroshimas every year (or more) and we see this energy being put to use in stronger and more frequent atmospheric disruptions like stronger winds, more violent and more frequent hurricanes, more torrential downpours and flooding, more droughts etc.
Bottom line: global warming isn't caused by your heater running, even if we run all the heaters in the world at the same time it still wouldn't heat up the planet in any measurable way. Instead, global warming is caused by earth absorbing tiny percent more of sun's energy, which is caused by increased greenhouse gasses, which is caused by burning fossil fuels. We can measure the planet's temperature, and we can measure how much energy it is absorbing and it all adds up.
