NRAL Conference Moscow 14 December 2012 A role

NRAL Conference, Moscow, 14 December 2012 A role of multi-decadal natural variability in forming weather and climate anomalies in Russia Major results in 2012 WP 5 Regional Projections of Extreme Events Vladimir A. Semenov vasemenov@mail. ru www. NRAL. org Natural Risks Assessment Laboratory

NRAL Conference, Moscow, 14 December 2012 Outline ● Recent harsh winters as a consequence of the Arctic sea ice melt ● Impact of Atlantic Multidecadla Variability on weather and climate ● Simulation of the hypothetical Gulfstream shutdown ● Winter Arctic Sea ice and the Early 20 th Century Warming ● Projections of regional climate changes (CMIP 5 models) ● Impact of model resolution on daily precipitation statistics www. NRAL. org Natural Risks Assessment Laboratory

NRAL Conference, Moscow, 14 December 2012 Harsh winters of the 21 st century: Anomalously cold monthly temperature after a period of mild winters in 1980 s and 1990 s 1988 -2002 period Hamburg “cold yrs” < 0 °C Moscow “cold yrs” < -9 °C N N p p 1950 -1987 11 0. 29 18 0. 47 1988 -2002 1 0. 07 2 (3) 0. 25 (0. 33) 3 (4) 0. 36 (0. 44) 2003 -2010 (11) www. NRAL. org Natural Risks Assessment Laboratory

NRAL Conference, Moscow, 14 December 2012 Harsh winters of the 21 st century: The most recent example of winter 2012 SAT anomaly, K SLP anomaly, h. Pa Previously, using idealized simulations with an AGCM, it was found that anti-cyclonic atmospheric circulation response can be caused by reduced sea ice anomalies in the Barents and Kara Seas (Petoukhov and Semenov 2010) Can it be reproduced by using realistic sea ice anomalies? www. NRAL. org Natural Risks Assessment Laboratory

NRAL Conference, Moscow, 14 December 2012 Modeling climate response to the sea ice changes corresponding to the recent extremes of the Atlantic Multidecadal Variability Experimental setup SST anomalies in the NA (40 N-60 N) www. NRAL. org Natural Risks Assessment Laboratory SST and SIC changes (1998 -2006)-(1968 -1976)

NRAL Conference, Moscow, 14 December 2012 Modeling climate response to the sea ice changes corresponding to the recent extremes of the Atlantic Multidecadal Variability Sea ice impact on circulation and temperature winter SAT Sea ice reduction in the Atlantic sector of the Arctic leads to the temperature decrease due to anti-cyclonic circulation anomaly centered in the southern border of the Barents Sea (Semenov et al. 2012, FAO) www. NRAL. org Natural Risks Assessment Laboratory winter SLP winter 2012

NRAL Conference, Moscow, 14 December 2012 Modeling climate response to the sea ice changes corresponding to the recent extremes of the Atlantic Multidecadal Variability Changes in probability of the anomalously cold februaries, in % (SAT less than 1. 5 standard deviation) www. NRAL. org Natural Risks Assessment Laboratory

NRAL Conference, Moscow, 14 December 2012 Realistic sea ice experiments: sea ice vs NAO ECHAM 5 -T 42 L 19/fixed. SST-SIC run 781: SIC <1966 -1969>, SST <1981 -2000> : high ice, very low NAO, cold winters run 782: SIC <1990 -1995>, SST <1981 -2000> : low ice, very high NAO, warm winters run 783: SIC <2005 -2008>, SST <1981 -2000> : very low ice, low NAO, cold winters www. NRAL. org Natural Risks Assessment Laboratory

NRAL Conference, Moscow, 14 December 2012 Realistic sea ice experiments: sea ice vs NAO • No significant response to sea ice change from 1966 -1969 to 1990 -1995 • “Anti-cyclonic” response to sea ice changes from 1990 -1995 to 2005 -2010 similar to observations (although seasonally shifted) NCEP Jan SLP change (2005 -10)-(1990 -95) Semenov et al. (in preparation) www. NRAL. org Natural Risks Assessment Laboratory Realistic sea ice experiments: Feb SLP change SIC (2005 -10)-(1990 -95)

NRAL Conference, Moscow, 14 December 2012 Impact of Atlantic Multidecadal Variability on weather and climate (work with Evgeniya Shelekhova) ? www. NRAL. org Natural Risks Assessment Laboratory

NRAL Conference, Moscow, 14 December 2012 Impact of Atlantic Multidecadal Variability on weather and climate Experimental setup: Atmospheric GCM ECHAM 5 coupled with mixed layer ocean model with additional Q-fluxes corresponding to Atlantic Multidecadal Variability ATLICE ATL www. NRAL. org Natural Risks Assessment Laboratory ATLICEx 2 ICE

NRAL Conference, Moscow, 14 December 2012 Impact of Atlantic Multidecadal Variability on weather and climate Winter SLP changes, h. Pa ATLICEx 2 ICE Atmospheric circulation response depends on both the amplitude and location of the additional heating. It is heat flux that is associated with sea ice changes that produces NAO-like response. www. NRAL. org Natural Risks Assessment Laboratory

NRAL Conference, Moscow, 14 December 2012 Impact of Atlantic Multidecadal Variability on weather and climate Change in probability of anomalously cold Februaries (colder than -1. 5 standard deviation, in %) ATLICEx 2 ATL ICE AMV may lead to increased probabilities of the cold winter months in large regions of Russia, in particular in European part. The increase is likely due to Arctic sea ice loss associated with the AMV. www. NRAL. org Natural Risks Assessment Laboratory

NRAL Conference, Moscow, 14 December 2012 Impact of Atlantic Multidecadal Variability on weather and climate Experimental setup: Atmospheric GCM ECHAM 5 coupled with mixed layer ocean model with additional Q-fluxes corresponding to Atlantic Multidecadal Variability The additional flux is time-varying with periodicity of 60 years Experiments: 1. ATLICEx 2 flux, 60 years period 2. ATLICE flux, 60 years period 3. ATLICE flux, 40 years period www. NRAL. org Natural Risks Assessment Laboratory

NRAL Conference, Moscow, 14 December 2012 Impact of Atlantic Multidecadal Variability on weather and climate Implications for the Caspian Sea level variations Annual temperature regression on the anomalous Q-fluxes (°С / 0. 1 PW) Volga River discharge (km 3/year) as simulated and observed Correlation and regression of annual precipitation with anomalous Q-fluxes (0. 1 mm / day / 0. 1 PW) correlation regression AMV can be an important factor for the Caspian Sea level variations Impact of Atlantic Multidecadal Variability on Caspian Sea level, Semenov et al. , EGU 2012 www. NRAL. org Natural Risks Assessment Laboratory

NRAL Conference, Moscow, 14 December 2012 The “Day after Tomorrow” revisited: Simulation of the hypothetical Gulfstream shutdown After a possibility of the Atlantic Meridional Overturning shutdown due to global warming with a threat of new Ice Age was disproved some years ago, recently, another media event has happened: Gulf of Mexico Oil Spill in spring 2010. Loop Current breaks, Gulfstream stops, Europe freezes and suffer from extremes. www. NRAL. org Natural Risks Assessment Laboratory

NRAL Conference, Moscow, 14 December 2012 Simulation of the hypothetical Gulfstream shutdown Deviation of surface temperature from zonal means, K Annual oceanic heat transport (Q-flux in the MLO model), W/m 2 www. NRAL. org Natural Risks Assessment Laboratory

NRAL Conference, Moscow, 14 December 2012 Simulation of the hypothetical Gulfstream shutdown Simulated January temperature change, K Atlantic sector January 2006 Barents Sea Zuev, Semenov, Shelekhova, Gulev, Koltermann, 2012, Doklady Earth Sciences www. NRAL. org Natural Risks Assessment Laboratory

NRAL Conference, Moscow, 14 December 2012 Winter Arctic Sea ice and the Early 20 th Century Warming There is a clear disagreement between temperature and sea ice Had. ISST 1 data in the Arctic in before 1960 s. Using AGCM with prescribed boundary conditions (sea ice and SST) allows us to evaluate temperature sensitivity to sea ice and estimate Arctic sea ice anomaly in the Early 20 th century Warming period Semenov, Latif, 2012, TC www. NRAL. org Natural Risks Assessment Laboratory

NRAL Conference, Moscow, 14 December 2012 Winter Arctic Sea ice and the Early 20 th Century Warming 0. 8 млн км 2 Difference between observed and simulated (Had. ISST 1 ice data) Arctic land winter (November-April) temperatures, °C Negative Arctic sea ice anomaly in the ETCW period is comparable to the current sea ice decrease www. NRAL. org Natural Risks Assessment Laboratory

NRAL Conference, Moscow, 14 December 2012 Projections of regional climate changes Using data of 9 CMIP 5 models, monthly mean temperature and precipitation, daily max and min temperature has been analyzed in simulations employing moderate climate change scenario RCP 4. 5. Annual SAT (°C) for Sochi region as simulated by 9 CMIP 5 models in the 21 st century www. NRAL. org Natural Risks Assessment Laboratory Ensemble mean (for 9 CMIP 5 models) annual SAT (°C) for Sochi region in the 21 st century. Dashed area represents 95% confidence interval

NRAL Conference, Moscow, 14 December 2012 Projections of regional climate changes Same as in the previous slide but for precipitation, mm/day winter summer www. NRAL. org Natural Risks Assessment Laboratory spring fall

NRAL Conference, Moscow, 14 December 2012 Projections of regional climate changes Ensemble mean annual precipitation trends and their uncertainty Trend, mm/day per 100 yr Inter-ensemble STDDEV, mm/day per 100 yr www. NRAL. org Natural Risks Assessment Laboratory

NRAL Conference, Moscow, 14 December 2012 Impact of model resolution on daily precipitation statistics What is the impact of the climate model resolution on the results we use for climate change assessments? T 31 T 63 T 159 www. NRAL. org T 42 T 106 T 213 Natural Risks Assessment Laboratory

NRAL Conference, Moscow, 14 December 2012 Impact of model resolution on daily precipitation statistics Summer mean precipitation, mm/day www. NRAL. org Natural Risks Assessment Laboratory Summer rain intensity, mm/day

NRAL Conference, Moscow, 14 December 2012 Impact of model resolution on daily precipitation statistics Impact on extremes 20 -yr return values of daily precipitation in the Gelendzhik region, mm/day as a fuction of model resolution (in degrees lat/lon) www. NRAL. org Natural Risks Assessment Laboratory

NRAL Conference, Moscow, 14 December 2012 Major conclusions § Recent anomalously cold winters can be a consequence of the Arctic sea ice loss. Winter sea ice retreat plays the major role in forming anticyclonic atmospheric circulation anomaly leading to cold events. § Accelerated winter Sea ice loss may be linked to the Atlantic Multidecadal Variability. § Atlantic Multidecadal Variability (AMV) plays important role for climate change over Eurasia, it can be responsible for about a half of the observed climate change in the last 3 -4 decades. § AMV impacts not only mean climate characteristics but also extreme events. § Global climate model projections on a regional scale have a very large spread and should be treated with caution. § To resolve regional peculiarities related to complex orography and coastal line, a higher spatial resolution is required than that provided by current generation of global climate models. www. NRAL. org Natural Risks Assessment Laboratory

NRAL Conference, Moscow, 14 December 2012 Спасибо за внимание! www. NRAL. org Natural Risks Assessment Laboratory

NRAL Conference, Moscow, 14 December 2012 Publications 2012 Refereed journals Зуев В. В. , Семенов В. А. , Шелехова Е. А. , Гулев С. К. , Колтерманн П. Оценки влияния океанического переноса тепла в Северной Атлантике и в Баренцевом море на климат Северного полушария // Доклады РАН. 2012. Т. 445. № 5. С. 585– 589. Семенов В. А. , Мохов И. И. , Латиф М. Влияние температуры поверхности океана и границ морского льда на изменение регионального климата в Евразии за последние десятилетия. // Изв. РАН Физика атмосферы и океана. 2012. Т. 48. № 4. С. 403 -421. Semenov V. A. , Latif M. The early twentieth century warming and winter Arctic sea ice // The Cryosphere. 2012. V 6. Doi: 10. 5194/tc-6 -1 -2012. Conferences Semenov, V. A. , Mokhov, I. I. , Latif, M. and K. P. Koltermann (2012) Impact of Atlantic Multidecadal Variability on Caspian Sea level, EGU General Assembly 2012, Geophysical Research Abstracts, Vol. 14, EGU 2012 -10897. Semenov, V. A. and M. Latif (2012) The early twentieth century warming and winter Arctic sea ice, EGU General Assembly 2012, Geophysical Research Abstracts, Vol. 14, EGU 2012 -10287. www. NRAL. org Natural Risks Assessment Laboratory

NRAL Conference, Moscow, 14 December 2012 www. NRAL. org Natural Risks Assessment Laboratory