Our top story on Midday edition. San Diego is bracing for a week of very hot weather and excessive heat warning is in effect today through tomorrow across southern California including San Diego's inland valleys and mountains. Highs are expected in the triple digits but during the last few weeks of higher than normal temperatures. It's not just the inland areas that have gotten unusually hot. It's also the ocean. In recent days scientists at Scripps Institution of Oceanography have been recording the highest ocean temperatures in their 102 years of taking readings off Scripps Pier. Joining me is Scripps Institution of Oceanography researcher Melissa Carter. And Melissa welcome to the program. Thank you. Glad to be here. What are the readings that are breaking records. Yeah so we have a couple of different programs. One is a manual record it's a historical record that's been collected since 1916 when Scripps Pier was originally built and we've continued collecting data because it's actually a very unique data set and the way that those data are collected and we've been breaking the surface temperature records pretty much this last week where now we're seeing temperatures as high as 70 eight point eight degrees Fahrenheit. We also have automated sensors that are tracking temperature continuously or every at a very high frequency interval like four minutes. And so those can be recording potentially higher temperatures instead of the once per day measurement that's done by the manual measurements. How's the ocean been getting warmer for the last couple of years. So there's been extreme heating since 2014 and then 20 16 2017. There was a blob that had occurred which is a much larger scale warming and extreme temperatures that were found in the in the Pacific. And then we saw temperatures basically come back to normal here in 2018 in the spring of 2018. We saw them come back to average and then now since July they've been increasing and going back up into these very extreme ranges again. Do we know why. That's a great question. So this is part of the chicken or egg. So there's these high pressure systems that are setting up and so is the ocean warmer as it is in the atmosphere. That's then. So we're seeing high sea surface anomalies that are happening that keep the ocean from basically releasing that heat out of it. So the heat stays and and and whenever the ocean starts warming you get stratification as a stratification can continues to get stronger. We have less mixing with with deeper water which is generally colder water. So it basically amplifies though the warming is this an effect of climate change. Climate change is seen a warming over time and our measurements at Scripps Pier what we've seen is we have a one point eight degree Fahrenheit increase in sea surface temperature over the last hundred years. That's what we've observed. So that's very consistent than as what the predictions are for climate change. But then on top of that we're also seeing these extreme warming events and those potentially can get more extreme with warming. How valuable is this data to the work that you do the data you collect every day at Scripps Pier. This data is actually really critical to put these events in a long term perspective. Most data sets that are around that are actually looking at what they call long term change only started in 1983 with satellites. So that's the basis whenever a lot of comparison is done it's done over a 30 year period. So we have a very unique record that goes back to 100 years. All data sets have some flaws to them and ours is one that's just measured on a daily basis. But one thing that is similar about this data sets collected this the same way over time. And so it does provide some way to compare over a longer span of time. Now here we are only in early August. Do you expect the ocean temperatures to continue to rise during this month. Yes. Generally August is our warmest month for ocean temperatures. So I would expect that we are going to continue to be breaking these records. One of the other things that we've been seeing in the last few years where we have these warm events is that our winter months are also becoming very warm as well. So they're becoming more similar to our summer months which is something that is consistent with what happens during periods of El Nino. And so we we will see. There is potential to see more impact and the longer these warming events last the more impact to the biological systems that we have. I've been speaking with Scripps Institution of Oceanography researcher Alyssa Carter and Melissa thank you. Thank you. Maureen.
Southern California faces yet another heat wave this week.
National Weather Service forecasters have issued an excessive heat warning in San Diego County from 10 a.m. Monday to 8 p.m. Tuesday, as temperatures were expected to soar as high as triple-digits everywhere except the immediate coast across a large swath of the Southland from Santa Barbara to San Diego and even stretching into Nevada.
High temperatures near the county shoreline will be in the mid-to-upper 80s today and Tuesday, while temperatures were expected to reach into the high 90s today in locales region-wide and the 100s in Escondido, Ramona and Alpine, with temperatures a few degrees cooler on Tuesday.
A high of about 113 degrees has been predicted for Borrego Springs on both days.
The heat is expected to subside midweek, with a return of humid conditions expected through the weekend.
"Some monsoonal moisture will return beginning Wednesday with high temperatures not quite as extreme," the NWS said.
The weather service and law enforcement caution that those who work outdoors should avoid the midday sun, wear light, loose-fitting clothing and drink plenty of water.
Nighttime lows will be in the mid 80s in the county deserts, meaning the minimal cooling at night could pose a health risk to those who don't have access to air conditioning because the body needs time to cool down from the day's heat, according to the NWS.
Avoid leaving senior citizens and kids at home without air conditioning, if possible. And never leave a child, senior or pet in a parked vehicle, even with windows cracked open, because interior temperatures can quickly turn lethal.
