Bits of Climate

Understanding Sea Level Rise, p4: ice sheet dynamics and (13) melting feedbacks – a background to 21st century SLR acceleration

In 2016 two influential new publications raised the possibility of a rapid acceleration of sea level rise in the 21st century – to ±2 metres (DeConto & Pollard) or more (2-5m, Hansen et al). In this background article we take … Continue reading →

Understanding Sea Level Rise, p3: it’s about timescales, speed of change & carbon budget – world aims for 29-55m sea level rise

In our previous article of the series we’ve looked at an overview of global sea level rise forecasts for the year 2100 – and seen that these forecasts have a very large spread, and also seem to increase with time … Continue reading →

Understanding Sea Level Rise, p2: A short chronology of SLR forecasts for the year 2100 (showing they increase with time)

Sea level rise is a slow process. Other consequences of climate change are generally felt much sooner. But there is something odd about the forecasts. They seem to be catching up with us, bringing a distant future closer to our … Continue reading →

Understanding Sea Level Rise, part 1: Thermal Expansion – a Physical Foundation of several metres, irrespective of ice melting

In between our series about the global temperature trend and our (upcoming) series about climate & biodiversity, let’s do a short series about sea level rise, shall we?

Do the math! Because climate sensitivity is logarithmic, 1.5 degrees target was already breached at 400 ppm – if you look at CO2 only (& assume ECS = 3C)

According to ‘conventional climate science’ the currently already emitted amount of CO2 (404 ppm) leads to a committed warming of 1.56 degrees Celsius. To keep ‘the promise of Paris’ – the CO2 concentration must go down, down to below 400 … Continue reading →

Observed vs ‘Real’ Global Temperature. What thermometers do & don’t yet show!

After a perceived ‘temperature plateau‘ of about a decade, global temperatures seem to be rising faster than ever before. First 2014 broke the global record for hottest year (then held by 2010). Then 2015 broke that record. And 2016 in … Continue reading →

Real Global Temperature Trend, p25 – Paleoclimate experts to the rescue! Closer to 1-2 degrees Celsius in pipeline from long-term climate inertia

We would keep the story simpler, helpful real-world paleoclimate experts advise us: ‘Say the Pliocene was 2 to 3 degrees warmer than pre-industrial Holocene – at a CO2 concentration that is about as high as the one that’s currently measured, … Continue reading →

Real Global Temperature Trend, p24 – Paleoclimate tells we may have 3 degrees additional warming in pipeline at current CO2 concentration!

Either the entire world is set to experience dramatic additional warming once we stabilise at the current (400+ ppm) CO2 concentration – or we are still dramatically underestimating the local climate sensitivity of the Arctic – a region that might … Continue reading →

Real Global Temperature Trend, p23 – Climate sensitivity has large geographical spread: 2-3 degrees global average equals 6+ in the Arctic

Why climate change is such a killer? Because disruption is never a linear process. We see that with ecosystem disintegration – where beyond a certain threshold cascading damage sets in – leading to shifts and collapse scenarios that are easy … Continue reading →

Real Global Temperature Trend, p22 – World still on course for dramatic 3 degrees warming, need to more than double reduction speed

Let’s keep this one short, because in essence there’s nothing new. Before the start of the Paris climate summit we saw that if you combine all the world’s nations’ 2025 & 2030 emission reduction targets you get to a pathway … Continue reading →